'Block' was a British amphibious undertaking to destroy the last remnants of the Japanese forces on Ramree island off the Arakan western coastal region of Burma after the landing of Brigadier R. C. Cottrell-Hill’s Indian 71st Brigade of Major General C. E. N. Lomax’s Indian 26th Division in 'Matador' (iii) within the 'Talon' overall plan, which also included 'Sankey', 'Pendant' and 'Mike' (8/22 February 1945).
'Block' was launched from Chittagong and the Naf river, and was preceded by the 'Matador' amphibious undertaking which started on 21 January 1945 under cover of the battleship Queen Elizabeth, the light anti-aircraft cruiser Phoebe, the destroyers Rapid and Napier, and the sloops Flamingo and Indian Kistna, with air support from the Republic Thunderbolt single-engined heavy fighters and North American Mitchell twin-engined medium bombers of Air Commodore the Earl of Bandon’s No. 224 Group as well as some 85 Consolidated Liberator four-engined heavy bombers of Air Commodore F. J. W. Mellersh’s Strategic Air Force.
The 71st Brigade landed without opposition west of Kyaukpyu at 09.42. There was a measure of confusion after the leading motor launch and a landing craft were blown up after striking mines, but order was soon restored and the landing went in a mere 12 minutes late and by the afternoon of the same day the beach-head had been secured. On 22 January Brigadier J. F. R. Forman’s Indian 4th Brigade of the same division came ashore, assumed control of the beach-head and occupied Kyaukpyu. One day later the 71st Brigade began to move to the south along Ramree’s western coast, occupying Mayin on 25 January and reaching the Yanbauk Chaung on 26 January. By this time opposition was stiffening from what had by now been identified as the 2/121st Regiment of Lieutenant General Shigesaburo Miyazaki’s 54th Division in Lieutenant General Shozo Sakurai’s 28th Army.
On the same day Royal Marines landed in 'Sankey' on Cheduba island, off the south-western side of Ramree island, only to find the island deserted. On 31 January Lomax sought to bypass the Japanese holding the Yanbauk Chaung, now pinned by the Indian 4th Brigade, and thus ordered his 71st Brigade to cross north-east across the island to Sane and them turn south once more toward the town of Ramree. By 1 February the 71st Brigade had entered Sane and units of the 26th Division’s reserve, Brigadier L. G. Thomas’s Indian 36th Brigade, had occupied Sagu Kyun island off the southern tip of Ramree island and relieved the Royal Marines on Cheduba island.
As a result of the instruction issued by Lieutenant General Sir Oliver Leese, commander-in-chief of the Allied Land Forces, South-East Asia, for an enlargement of the operations in Arakan, Lieutenant General Sir Philip Christison, commanding the Indian XV Corps of which the 26th Division was a part, ordered Lomax on 4 February to start 'Block' and so destroy Ramree island’s Japanese garrison, wholly clear the smaller islands between Ramree and the mainland with the help of the available naval forces, and undertake raids on the coast between Taungup and the An river in a concerted effort to disrupt the Japanese line of communication to the north and also to establish the Japanese strength and dispositions in the Taungup area. Lomax was also informed that he was not required to garrison Cheduba island and that Brigadier R. F. Johnstone’s 22nd (East Africa) Brigade, of the corps reserve, would be sent to Kyaukpyu to come under his command and garrison Ramree island.
On 7 February, the 71st Brigade, with armoured support, reached the western side Ramree town and met strenuous opposition. The 4th Brigade, which had pushed past the Yanbauk Chaung to reach the Ledaung Chaung, was now instructed to wheel east and assist the 71st Brigade, and on 9 February the two brigades succeeded in occupying Ramree town.
Supported by naval elements, the 26th Division then turned its attention to 'Block', which was designed to prevent the surviving Japanese forces from escaping to the east by blocking the escape routes from the many chaungs on the low-lying eastern side of the island to the mainland.
'Block' was a true combined operation. While the navy used destroyers, yard minesweepers, motor launches, medium support landing craft and assault landing craft to block all the chaung exits between Taraung Chaung to the Pakseik Taungmaw river the east, and the exits into the Mingaung Chaung and the Pakseik Taungmaw river in the north-east, the army covered the chaung exits south to the Taraung Chaung by means of an advance to the north from Kyauknimaw with the Indian 36th Brigade, and also occupied Kalebon to close the possible Japanese escape routes to the north between Sane and the Mingaung Chaung, and the air force strafed boat concentrations and provided cover. Thus the army and air force effectively drove the Japanese remnants off Ramree island into the mangrove swamps.
The navy established its blocks by placing the support and assault landing craft, camouflaged with foliage, in ambush positions at the mouth of the chaungs, while the motor launches and yard minesweepers were used as back stops. Initially there were two naval blocks known as the North Block (along the course of the Mingaung Chaung and the Pakseik Taungmaw river) and the South Block (from Tan Chaung to the Taraung Chaung). However, as operations proceeded and more intelligence was received of the Japanese intentions, the South Block was moved to form an East Block (from the lower Zareik Chaung to the upper Didokbank) and later again moved to form the Thanzit Block (from the Wonkpit Chaung to the Awlebyin river). In the later stages the chaungs were illuminated at night and a greater degree of mobility of craft was introduced.
The frontage covered in these operations was considerable. Exits from the mangrove swamps were not confined to those which had been marked on the maps which were available, and hundreds of chaungs and waterways were found to be in existence, all suitable for use by local craft, and trees with thick foliage growing down to the water’s edge provided ample cover for any small boat. At high water much of the mangrove area was flooded, allowing lateral movement from one chaung to another. The rise and fall of the tide, accentuated by conditions of shallow water and mud near the banks, made concealment of landing craft difficult. When the process of blocking the chaungs began, the moon was in its first quarter and the tide approaching springs. All these conditions were to the advantage of the Japanese.
However, the disadvantages to the Japanese lay in the horrors of the mangrove swamps. These were dark by day as well as by night, and comprised acres of impenetrable forest and deep glutinous black mud crawling with mosquitoes, scorpions, flies and a host of other noxious insects and, worst of all, crocodiles. Neither food nor drinking water was obtainable. It can hardly be possible that in their decision to try to leave the island the Japanese could have been fully aware of the appalling conditions which prevailed, and it proved to beyond even the vaunted endurance of the Japanese for their men to exist for more than a few days. Prisoners taken out of the mangroves during the operations were found to be semi-dehydrated and in a very poor physical condition.
The crews of the minor landing craft, with army machine gun units embarked, also had a hard time. It was found possible to relieve the army personnel about every four days, but as a result of the shortage of spare crews, many of the Royal Marines and sailors had to remain in their craft for the entire 14 days of 'Block'. The provision of these widespread units with food, water, cigarettes, etc., and their craft with fuel and repair facilities, presented a formidable administrative problem, but largely by the allocation of a yard minesweeper or a large infantry landing craft as a 'mothership' for each block and by the co-operation of the army, these difficulties were overcome and after the first few days the standard of rations became, on the whole, quite acceptable.
In an attempt to break the blockade the Japanese launched an air attack on 11 February, seriously damaging one destroyer, and despatched a flotilla of about 40 small craft to rescue the survivors of the Ramree garrison. Resistance on Ramree island ended on 17 February, but the blockade was maintained for another five days, inflicting severe losses on the Japanese small craft and their payloads in the eastern chaungs. Even so, the Japanese managed to extract about 500 of the estimated 1,200 to 1,500 men who had formed the garrison on 8 February. The others were either killed in battle or drowned in the mangrove swamps. Only 20 prisoners were taken in spite of all efforts of persuasion toward the end of 'Block', by which time many Japanese troops, without hope of relief or escape, had reached the terminal stages of exhaustion.