The 'Battle of the Malacca Strait' was a naval battle that resulted from the British 'Dukedom' search-and-destroy operation and culminated in the sinking of the Japanese heavy cruiser Haguro (15/16 May 1945).

Haguro had been operating as a supply ship for Japanese garrisons in the Netherlands East Indies and the Bay of Bengal since 1 May 1945.

On 9 May, Haguro departed Singapore, escorted by the destroyer Kamikaze, to evacuate the Japanese garrison of the Andaman islands group, centred on Port Blair, for transport back to Singapore. The Royal Navy was alerted to this undertaking by a decrypted Japanese naval signal, which was subsequently confirmed by a sighting by the submarines Statesman and Subtle. Force 61 of Admiral Sir Arthur Power’s East Indies Fleet steamed from Trincomalee, in Ceylon, on 10 May with orders to intercept and sink the Japanese force. The Japanese were unwilling to risk battle and, on receipt of an air reconnaissance warning, turned back toward Singapore.

On 14 May, Haguro and Kamikaze made a second attempt to evacuate the Andaman islands' garrison, and left Singapore, but on the following day the two ships were spotted by aircraft from Force 61. The subsequent bombing attack by Grumman Avenger Mk II single-engined aircraft of the Fleet Air Arm’s No. 851 Squadron inflicted only minor damage on Haguro for the loss of one aeroplane whose crew was taken prisoner by the Japanese.

Information was relayed to the Japanese that two British destroyer squadrons had been sighted heading toward their two ships and, once gain, the Japanese ships reversed course to return to Singapore via the Malacca Strait between Malaya and the island of Sumatra. This change had been anticipated, however, and the 26^th Destroyer Flotilla, under the command of Captain M. L. Power, steamed to intercept with Saumarez (flag), Verulam, Venus, Vigilant and Virago.

In heavy rain squalls with lightning, Venus established radar contact with the Japanese ships at a range of 39 miles (63 km), and the British destroyers then deployed into a crescent cordon and allowed the Japanese ships to sail into the trap.

At 01.05 Venus, parallel with Haguro as the Japanese ship raced past the north-westernmost ship in Power’s force, found herself in a perfect attacking position. The torpedo control officer on Venus had made the wrong angle settings on the British destroyer’s eight tubes, however, the opportunity was lost and Venus heeled hard to port in order to clear the target area but still maintain the encirclement. Believing that Venus had launched torpedoes, Haguro altered course away to comb the tracks, but in doing so turned to south and thus deeper into the British trap.

Saumarez and Verulam were now well positioned to make their attacks. Haguro appeared fine off Saumarez's port bow at a range of 6,000 yards (5485 m), each ship making 30 kt. At the same time, the Japanese destroyer Kamikaze appeared off the starboard bow, crossing from starboard to port, only 3,000 yards (2745 m) distant and on a collision course. Saumarez's second salvo from her two forward, radar-controlled 4.7-in (119.4-mm) guns struck Kamikaze and 40-mm Bofors shells from the British ship’s after twin mounting ripped the 320-ft (97.5-m) length of the Japanese destroyer as Saumarez heeled to starboard. Haguro now fired her first broadside of 10 8-in (203.2-mm) and four 5-in (127-mm) guns at Saumarez. Huge spouts of water thrown up alongside swamped the British flotilla leader’s upper decks as Haguro was seen clearly 5,300 yards (4845 m) away in the light of both sides' star shells.

At 01.11, just as she was about to fire torpedoes, Saumarez was hit. The top of her funnel disappeared over the side and a 5-in (127-mm) shell penetrated No. 1 boiler room, severed a steam main and lodged inside the boiler. Five men were scalded, of whom two later died, but as with the earlier 8-in (203.2-mm) shell hits, this projectile failed to detonate at such close range and was later thrown overboard.

At 01.15, Haguro was struck by three torpedoes from Saumarez and Verulam. As the former limped northward from the immediate battle area, a violent explosion created confusion. Power thought it was Kamikaze blowing up, and men on Virago and Vigilant believed that it was Saumarez, but it was probably two torpedoes colliding. Venus hit Haguro with one torpedo at 01.25, and Virago stopped Haguro with two more torpedo hits two minutes later. The Japanese heavy cruiser finally sank at 02.06 after receiving another torpedo from Vigilant, two more from Venus, and nearly an hour of gunfire from the destroyers of the 26^th Flotilla.

Saumarez's main aerial and a funnel top had been shot away, and an 8-in (203.2-mm) shell had nicked the forecastle. Two men had been killed and three burned in the boiler room when a 5-in (127-mm) shell severed the main steam pipe. There was no damage to the other destroyers of the 26^th Flotilla.

Kamikaze was also damaged but escaped, returning on the following day to rescue survivors. About 320 men survived, but more than 900 had died, including the Japanese commanders, Vice Admiral Shintaro Hashimoto, commander of the 5^th Cruiser Division, and Rear Admiral Kaju Sugiura, captain of Haguro.

The 'Battle of the Malacca Strait' was one of the last major surface gun and torpedo actions of World War II. Admiral the Lord Louis Mountbatten, himself a distinguished destroyer captain, described it in his report to the Combined Chiefs-of-Staff as 'an outstanding example of a night attack by destroyers'.