Under the command of Luitenant-kolonel Simon de Waal, the Dutch garrison of Tarakan was centred on the 7^th Battalion of three 177-man companies with 18 machine guns, one machine gun company with between 18 and 24 Vickers machine guns and six 80-mm (3.15-in) mortars, and one 80-man motorised detachment with seven overvalwagen armoured cars. Artillery support was provided by three coastal artillery batteries with three 75-mm (2.95-in) guns near Peningki and four 120-mm (4.72-in) guns at Karoengam with four more 75-mm (2.95-in) guns in reserve, two static artillery batteries with three 75-mm (2.95-in) guns near Lingkas and two old 70-mm (2.76-in) guns also near Lingkas, two anti-aircraft batteries with four 40-mm 4 × 40 mm guns and four 20-mm cannon, and four anti-aircraft machine gun platoons with 10 to 12 12.7-mm (0.5-in) heavy machine guns. Also available were two engineer platoons (one of 30 men and the other of 40 conscripted BPM men, and a mobile auxiliary first-aid platoon.

The Dutch air strength comprised naval aircraft in the form of the 304^th Militaire Luchtvaart’s three Martin B-10 twin-engined bombers that were transferred to Samarinda II Airfield in December 1941 as Tarakan airfield was deemed too small for twin-engined bombers, and four Brewster Buffalo single-engined fighters.

The Dutch naval strength was based on the minelayer Prins van Oranje together with two patrol boats, three Dornier Do 24K twin-engined flying boats and one government-owned light ship.

The Dutch plan before 1941 called for the defence of the oilfields and installations at all costs. If deemed impossible, Dutch forces were to deny any opponent the use of Tarakan’s oil-producing machinery before withdrawing to mainland Borneo.

One major problem in the defense of Tarakan was the unsuitability of its airfield for the accommodation of both fighters and bombers. However, the Dutch plan also called for a strong defence of the airfield, a task that in light of the airfield’s small size and the Japanese military strength (especially in sea and air power) presented almost insuperable difficulties.

The deployment of the Tarakan garrison was based on the Dutch intention of preventing Japanese occupation of the port complex on the island’s western coast, and the defence positions took the form of several 'fronts' of double-fence barriers. The were the Lingkas Front defending the port complex, the Northern Front defending access points to the airfield as the support points in and around Tarakan airfield, and the Eastern Front defending the Pamoesian oilfield. There was no overland connection between the Eastern Front and the Northern Front, so special units guarded the gap between these two fronts.

On the eastern coast, Dutch troops prepared a platoon-strength support point at the mouth of the Amal river to impede any Japanese landing for a short time before retreating to the Eastern Front. Additional infantry covering forces were established at the Djoeata, Peningki and Karoengan batteries.

Each of the support points, on which the front was based, was held by a group of 25 men with two light and two medium machine guns. Based on a concrete pillbox, each support point was surrounded by a double fence, but the scarcity of the available troop strength made it impossible to occupy all the support points at the same time.

The coastal artillery batteries covered the minefields and the entrances to the harbour. The artillery of the Lingkas Front could also be used to support inland battles.

Initially, the airfield was defended only by 20-mm anti-aircraft cannon and machine guns. Abandoned before the Japanese landing, two sections of 40-mm anti-aircraft guns (each less one gun) stood at the airfield; the 20-mm guns were relocated to defend the Peningki and Karoengan batteries.

The Dutch navy laid large minefields in the approaches to the port. In the event of an attack, any sea lanes that were still open were to be blocked by the minelayer Prins van Oranje.

Despite all of these preparations, in the aftermath of the Japanese 'Ai' attack on Pearl Harbor, a defeatist atmosphere had already partially enveloped the defenders even though it was still well before any signs of a Japanese invasion.

For the capture of Tarakan, the Japanese planned for a double landing on the island’s eastern coast. The Right-Wing Unit was to land near the Amal river and destroy any Dutch force there. Without waiting for the completion of the landing phase, unit was to advance to the west through the jungle and launch a surprise attack to seize the Pamoesian oilfield. Upon securing Pamoesian, Yamamoto’s troops were then to advance to secure the installations at the Lingkas port before the Dutch could demolish it. The Left-Wing Unit was to land farther to the south at Tandjoeng Batoe and advance to the west in order to take the Peningki-Karoengan gun batteries before moving to Lingkas, bypassing the 2^nd Kure Special Landing Force at the airfield, to attack and capture the Gunung Cangkol and Djoeata oilfields and the Djoeata battery in the north of the island. Once these key points of Tarakan island had been cleared, the Japanese army was to pass responsibility for guard duties to the Japanese navy, and the force would be reassembled in Tarakan and its vicinity to prepare for the capture of Balikpapan farther to the south.

On 10 January 1942, after a Do 24K flying boat had spotted the approaching Japanese invasion fleet, de Waal ordered the destruction of all of the island’s oil installations, and engineer units blew the drill pipes, which caused an underground explosion that prevented the short-term use of the wells and the extraction of oil. By 22.00, 100,000 tons of oil had been engulfed by fire.

At 03.00 on 11 January, Sergeant Major C. P. E. Spangenberg, commanding the Amal river support point (with 53 troops) reported the sighting of landing vessels nearing the coast. At that point, the Right-Wing Unit began to land on the eastern coast.

Since the Dutch forces had arranged their dispositions to defend against attacks from the west, they were still uncertain about whether or not the Japanese forces concentrating on the eastern parts of the island constitute the main attacking force. Diversionary landings and manoeuvres were still being considered, even as another Japanese landing force was sighted at 05.00 by the Dutch group defending Tandjoeng Batoe, farther to the south of the Amal river.

The Right-Wing Unit, having mistaken the fires at the Gunung Cangkol oilfield for those of the Lingkasoil field to the south, landed between 2.5 and 3.7 miles (4 and 6 km) to the north of its planned landing point at mouth of the Amal river. Spangenberg’s group also mistook the Japanese landing vessels, which were circling at the time, as a direct landing attempt and ordered his men to open fire.

Reaching the Amal river by 05.00, the Right-Wing Unit attacked, outflanked and defeated Spangenberg’s pillboxes. With the 25 to 30 men left, Spangenberg withdrew to a new support point near the Pamoesian river. As fires from the oilfields rendered many support points useless, Spangenberg’s position became the main point of defence on the Eastern Front. Under the overall command of Kapitein A. C. Saraber, this became a rallying point for the retreating Dutch troops and made it possible for them to re-establish a front line. To support this line, the Dutch constructed a second front behind that of Saraber. Comprising some 650 men, the line was supported by Kapitein W. Everaars' Javanese machine gun company, Kapitein F. Treffer’s Ambonese soldiers and several overvalwagen vehicles. Everaar’s men had received no proper training, however, many of their machine guns malfunctioned and the company had virtually little ammunition, which was soon expended.

Meanwhile, from information obtained through the interrogation of captured soldiers, the Right-Wing Unit now advanced to the northern side of the Tarakan oilfields. As it approached the oilfields, the unit’s advance was slowed by artillery and mortar fire from Saraber’s support point. The Dutch attempted a counterattack, supported by artillery and led by Treffer’s company in their baptism of fire: the attack failed, and Treffer’s men could not advance beyond the second front line.

Frustrated by the Dutch resistance, Sakaguchi requested an air attack on the batteries at Djoeata in the north of the island and on Sadau island at the far west of Tarakan, in addition to the town of Tarakan for the following day. As night fell, both sides prepared to launch simultaneous attacks. de Waal planned for the last Dutch counterattack at 05.15 on the next day with all of his available personnel including engineers, ammunition staff, clerks and cooks. The Japanese seized the initiative, however, and launched a series of raids at the same time, Yamamoto’s troops managed to capture both lines of Dutch barracks. In the middle of the chaotic fighting, the Japanese killed many Dutch troops. Treffer was killed as his company made a retreat toward the Dutch headquarters, which the Right-Wing Unit failed to capture.

With supplies dwindling, the number of Dutch troops declining and communications with the coastal batteries breaking down, the Dutch decided to capitulate. At 07.30 on 12 January, de Waal despatched a man under a flag of truce to announce the surrender. Yamamoto immediately sent a message to Sakaguchi, stating that the Dutch commander and his men had announced their surrender at 08.20, so it was requested that Sakaguchi land at the Lingkas pier.

Kanauji’s Left-Wing Unit landed near Tandjoeng Batoe at 04.00 on 11 January, but by 17.00 on the same day its whereabouts were still virtually unknown to the invasion force. After landing, the Left-Wing Unit had tried to advance directly through the jungle toward the rear of the Karoengan battery. As a result of the dense vegetation and steep jungle terrain, however, the unit could advance only about 110 yards (100 m) per hour and was disorientated about its surroundings.

Meanwhile, as it became evident to the Dutch that the Japanese were attacking from the east rather than the west, de Waal relocated some of his forces to protect the Kaorengan and Peningki batteries. On the night of 11 January, Kapitein L. Bendeler’s company of 65 men left the town of Tarakan after being assigned to a position in the vicinity of Tandjoeng Batoe and there guard the paths leading to the batteries. Hindered by darkness, the company became lost in the jungle before running into the Left-Wing Unit: without firing a shot, Bendeler and half of his unit were captured, while the other half was promptly executed. When captured members of his unit refused to guide the Left-Wing Unit through the forest, they were tied together in groups and bayoneted at dawn. Bendeler and some of his officers were spared.

By 12.00 on 12 January, Kanauji had just managed to reach the rear of the battery. Yet as he had been unable to establish any contact, just before 00.00 on 11 January Sakaguchi ordered an infantry company under Lieutenant Colonel Namekata to land at the Left-Wing Unit's landing point and advance along the coast to seize the battery. Even though the unit managed to reached the forward edge of the battery’s location, it could advance no farther as a result of the rough terrain.

Even after the Dutch surrender, the breakdown of communication meant that the coastal batteries of Karoengan and Peningki did not know this. Advising caution, Sakaguchi sent a message to the navy to the effect that although the Dutch had offered to surrender, it was feared that the battery at the southern end of the island was not aware of this and it would be dangerous to proceed to the Tarakan Pier, and therefore that naval vessels should not attempt to berth at this pier.

Ignoring Sakaguchi’s warning, at 12.00 six minesweepers of the 11^th Minesweeper Division and 30^th Minesweeper Division departed and approached the Mengacu Channel to sweep the port area for mines. As soon as W-13 changed course toward Lingkas, the Karoengan batteries opened fire a a range of about 2,190 yards (2000 m). By the time the Dutch battery fired its third salvo, W-13 had received a direct hit midships near the waterline; W-14 now began to fire back and both ships increased their speed and headed toward Lingkas. After a second hit, W-13 received another hit near the bridge and began to turn toward the port. The ship took evasive action before stopping for a moment. As W-13 tried to turn back, her rudder seemed to be jammed. As W-13 began to take evasive action, the Dutch batteries turned their attention to W-14, which immediately took hits to her bridge, midships and stern. Before long, a shell hit the ship’s depth charges, the resulting explosion ripped through W-14 near her mizzen mast, while another shell blew off one of the ship’s two 120-mm (4.73-in) guns. Despite the damage, W-14 turned and steamed at full speed toward the Karoengan battery, her one gun still firing. As the vessel approached Cape Mengacu, a column of water thrown up at the waterline suggested that the minesweeper might have hit a mine. At 12.05, W-14 sank, bow first, near the shore at Cape Mengacu. The Karoengan battery immediately refocused its fire on W-13, now apparently heading toward Lingkas. As the minesweeper began to slow, Dutch fire began to become more accurate, for shells hit the ship’s bridge, destroyed one of its guns and caused massive fires. W-13 listed to port and began to go down by the bow, and sank at 12.15.

In addition to the two minesweepers, the Karoengan battery also sank a Japanese landing craft.As mines had been laid in the narrow waters of the engagement site, other Japanese ships could not swiftly rescue the survivors. The commander of the 11^th Minesweeper Division, Commander Wakito Yamakuma, was killed along with 156 of his men, while 53 sailors from both ships survived. The remaining four minesweepers were ordered to withdraw. Kanauji’s troops, hindered by poor communication and difficult conditions, managed to seize the Karoengan battery only at 17.10 on 13 January, the day after de Waal’s surrender.

On the night of 11 January, before Japan completed its naval blockade of Tarakan, the Dutch submarine K-X, the patrol boat P-1 and BPM motor schooner Aida slipped away to friendly waters. Camouflaged with palm leaves, P-1 reached the shore of Borneo and successfully navigated a series of waterways up the river to Samarinda.

The Dutch minelayer Prins van Oranje attempted to escape to the east, but at 21.57 the Japanese destroyer Yamakaze and the patrol vessel P-38, which were patrolling the waters to the north-east of Tarakan, spotted Prins van Oranje's silhouette and followed her eastward into wider waters. At 23.18, Yamakaze increased speed to 26 kt and began to close the Dutch minelayer. By 23.22, both ships opened fire on each other at an average range of a mere 1,970 yards (1800 m) and the engagement immediately became one-sided. Every salvo of Yamakaze's guns scored hits on Prins van Oranje, while the latter’s salvoes passed over the destroyer. Within 10 minutes Prins van Oranje had sunk, taking down with her 102 of her crew of 118 men. Yamakaze rescued 16 survivors and put them ashore in Tarakan.

Throughout the fighting for Tarakan, the Dutch made several air attacks from Samarinda II airfield in an effort to stem the Japanese attack. As a result of bad weather, particularly on 11 January, these efforts came too late for the defenders of Tarakan. On 10 January, six B-10 bombers and two Buffalo fighters sorted and for the loss of one B-10 shot down one Mitsubishi F1M 'Pete' reconnaissance floatplane. On 11 January three B-10 bombers and seven Boeing B-17 Flying Fortress bombers had to turn back as a result of the weather, but gunners of one of the B-17s short down a Mitsubishi A6M Reisen 'Zero' fighter. On 12 January 12 B-10 bombers, of which three aborted, lost one of their number while damaging to transport vessels and one destroyer, and shooting down two F1M floatplanes. On 13 January 15 B-10 bombers, of which two turned back, lost five of their number while damaging a light cruiser or destroyer and attacking Tarakan airfield.

By 13 January, the 'Sakaguchi' Detachment had rounded up all prisoners and captured equipment, and handed control to the navy on the following day. By this time the oil facilities at Tarakan had been substantially destroyed. In Lingkas, even though much of the oil had been consumed by fire, there were still 12,300 tons of heavy oil left in the surviving tanks, and 120 drums of heavy oil. By June 1942, the wells had been repaired and oil production continued without any serious hindrance until the middle of August 1943, when the first Allied air raids on Tarakan began.

Of the Japanese forces, the 'Sakaguchi' Detachment lost eight men killed and 35 wounded, the 2^nd Kure Special Naval Landing Force three men wounded, and the Japanese navy 247 men killed, 47 of them on land.

Some 300 Dutch soldiers were killed in the battle, and the Japanese took prisoner 871 men and interned another 40 wounded men. In addition, they seized nine anti-aircraft guns, 69 heavy machine guns, 556 rifles, 15 armoured cars, 67 motor cars and much ammunition. Some of the captured men managed to evade immediate capture and cross to mainland Borneo before being captured. Others hid in the Tarakan jungle before eventually falling into the same fate.

In retaliation for the loss of minesweepers W-13 and W-14, the Japanese executed many Dutch prisoners, particularly those from the Karoengan battery. On 18 January 215 prisoners were marched from the prisoner of war camp and drowned at sea at a location near the point at which the minesweepers had sunk or, according to another account, were beheaded or tied and thrown into the swamps to be eaten by crocodiles, by survivors of the two sunken minesweepers.

As noted above, Dutch warplanes flew bombing missions against Tarakan airfield from the Samarinda II base in eastern Borneo. However, repairs by engineers of the 2^nd Base Force had brought the airfield back into service by 16 January, when aircraft of the 23^rd Air Flotilla and Tinian Air Wing arrived from Jolo in the Philippine islands group. The airfield then became the staging point for the air support of the Japanese landing at Balikpapan.