After the fall of Rangoon, the Allies tried to make a stand in central Burma. It was hoped that the
Chinese Expeditionary Force in Burma, commanded by
Luo Zhuoying and consisting of the Fifth Army (commanded by
Du Yuming) and the Sixth and Sixty-sixth Armies, could hold a front south of
Mandalay. The Chinese armies each had approximately the strength of a British division but comparatively little equipment. Meanwhile, the newly created
Burma Corps which had been formed to relieve Burma Army headquarters of the day-to-day responsibility for operations and consisted of 1st Burma Division, 17th Indian Division and 7th Armoured Brigade, defended the
Irrawaddy River valley. Supplies were not immediately a problem, as much war material (including material originally meant for shipment to China) had been evacuated from Rangoon, rice was plentiful and the oilfields in central Burma were still intact, but no proper land routes from India existed and only the recapture of Rangoon would allow the Allies to hold Burma indefinitely. The Allies hoped that the Japanese advance would slow down; instead, it gained speed. The Japanese reinforced their two divisions in Burma with the
18th Division transferred from
Malaya and the
56th Division transferred from the
Dutch East Indies after the fall of
Singapore and
Java. They also brought in large numbers of captured British trucks and other vehicles, which allowed them to move supplies rapidly using southern Burma's road network, and also use
Motorised infantry columns, particularly against the Chinese forces. The Royal Air Force wing operating from
Magwe was crippled by the withdrawal of the radar and radio-intercept units to India and the Japanese soon gained supremacy in the air. Unopposed Japanese bomber fleets attacked almost every major town and city in the Allied-held part of Burma, causing widespread destruction and disorder. The rapidly expanding
Burma Independence Army harassed the Allied forces, while many Bamar soldiers of the Burma Rifles were deserting. The Allies were also hampered by the progressive breakdown of the civil government in the areas they held, and the large numbers of refugees. The flow of refugees began soon after the
bombing of Rangoon in late December 1941 and increased to a "mass exodus" in February 1942 as the Indian (and Anglo-Indian and Anglo-Burmese) population of Burma fled to India, fearing both the Japanese and hostile Burmese. Middle-class Indians and mixed-race refugees could often afford to buy tickets on ships or even planes, while ordinary labourers and their families in many cases were forced to make their way on foot. The commander of Burma Corps, Lieutenant General
William Slim, tried to mount a counter-offensive on the western part of the front, but his troops were repeatedly outflanked and forced to fight their way out of encirclement. The corps was gradually pushed northward towards Mandalay. The 1st Burma Division was cut off and trapped in the blazing oilfields at Yenangyaung, which the Allies themselves demolished to deny the facilities to the Japanese. Although the division was rescued by Chinese infantry and British tanks in the
Battle of Yenangyaung, it lost almost all its equipment and its cohesion. On the eastern part of the front, in the
Battle of Yunnan-Burma Road, the Chinese
200th Division held up the Japanese for a time around
Toungoo, but after its fall the road was open for
motorised troops of the
Japanese 56th Division to shatter the Chinese Sixth Army to the east in the
Karenni States and advance northward through the
Shan States to capture
Lashio, outflanking the Allied defensive lines and cutting off the Chinese armies from
Yunnan. With the effective collapse of the entire defensive line, there was little choice left other than an overland retreat to India or to Yunnan.
Allied retreat The retreat was conducted in horrible circumstances. Starving refugees, disorganised stragglers, and the sick and wounded clogged the primitive roads and tracks leading to India. At least 500,000 civilian fugitives reached India, while an unknown number, conservatively estimated between 10,000 and 50,000, died along the way. In later months, 70 to 80% of those who reached India were afflicted with diseases such as dysentery, smallpox, malaria or cholera, with 30% "desperately so". On 26 April the British, Indian and Burmese forces joined the civilians in a full retreat. The Burma Corps retreated to
Manipur in India. At one stage, Alexander proposed that the 7th Armoured Brigade and one infantry brigade accompany the Chinese armies into Yunnan, but he was persuaded that the armoured brigade would quickly become ineffective once it was cut off from India. The Japanese tried to cut off Burma Corps by sending troops by boat up the
Chindwin River to seize the riverside port of
Monywa on the night of 1/2 May. The hastily reconstituted 1st Burma Division was unable to recapture Monywa, but allowed the rest of the Corps to withdraw to the north. As the Corps tried to cross to
Kalewa on the west bank of the Chindwin by ramshackle ferries on 10 May, the Japanese advancing from Monywa attempted to surround them in a "basin" encircled by cliffs at
Shwegyin on the east bank. Although counter-attacks allowed the troops to escape, most of the Burma Corps' remaining equipment had to be destroyed or abandoned. On 12 May, the Japanese occupied
Kalewa, having covered in 127 days, fighting 34 battles. Burma Corps reached
Imphal in Manipur just before the
monsoon broke in May 1942. The
ad hoc Burma Corps HQ was disbanded and
IV Corps HQ, which had recently arrived in India, took over the front. The troops found themselves living out in the open under the torrential monsoon rains in extremely unhealthy circumstances. The army and civil authorities in India were very slow to respond to the needs of the troops and civilian refugees. Although the front-line units had maintained some semblance of order, many improvised units and rear-area troops had dissolved into a disorderly rout. The troops were in an alarming state, with "hair-raising stories of atrocities and sufferings". The British Civil Government of Burma had meanwhile fallen back to
Myitkyina in Northern Burma, accompanied by many British, Anglo-Indian and Indian civilians. The Governor (
Reginald Dorman-Smith) and the most influential civilians were flown out from Myitkyina Airfield, with some of the sick and injured.The majority of the refugees at Myitkyina were forced to make their way to India via the unhealthy
Hukawng Valley and the precipitous forested
Patkai Range. Many died on the way, and when they reached India, there were several instances in which civil authorities allowed white and Eurasian civilians to continue while preventing Indians from proceeding, effectively condemning many to death. By contrast, many private individuals such as the Assam Tea Planters Association did their best to provide aid. The Japanese advance cut off many of the Chinese troops from China. Many of them also retreated to India via the Hukawng Valley route and subsisted largely by looting, further increasing the misery of the refugees. The Chinese 38th Division however, commanded by
Sun Li-jen, fought its way westward across the Chindwin, arriving at Imphal on 24 May, substantially intact although with heavy casualties. The American General
Joseph Stilwell also made his way to Imphal on foot, arriving on 20 May. The remaining Chinese troops tried to return to
Yunnan through remote mountainous forests but many died on the way. The 23,000 Chinese soldiers who had retreated into India were put under the command of General Stilwell and were concentrated in camps at Ramgarh in
Bihar. After recuperating they were re-equipped and retrained by American instructors.
Panlong Subtownship, a Chinese Muslim town in
British Burma, was entirely destroyed by the Japanese forces during their invasion. The
Hui people,
Ma Guanggui became the leader of the Hui Panglong self-defense guard created by the Kuomintang government of the Republic of China. The Japanese burned Panglong, driving out the over 200 Hui households out as refugees. Yunnan and Kokang received the refugees from Panglong. One of Ma Guanggui's nephews was Ma Yeye, a son of Ma Guanghua and he narrated the history of Panglong including the Japanese attack. An account of the Japanese attack on the Hui in Panglong was written and published in 1998 by a Hui from Panglong called "Panglong Booklet".The Japanese attack caused the Hui Mu family to seek refuge in Panglong but they were driven out again to Yunnan when the Japanese attacked Panglong.
Halt to operations The Japanese 18th and 56th Divisions pursued the Chinese into Yunnan, but were ordered to halt on the
Salween River on 26 April The Japanese 33rd Division likewise halted on the Chindwin at the end of May, ending the campaign until the end of the monsoon rains. In the coastal
Arakan Province, some of the Burma Independence Army reached
Akyab Island before the Japanese troops. However, they also instigated
inter-communal fighting between the
Buddhist and
Muslim populations of the province. The Japanese advance in Arakan ended just south of the Indian frontier, prompting the British military and civil authorities in and around
Chittagong to implement a premature "scorched earth" policy which contributed to the
Bengal Famine of 1943. ==Thai occupation of Kayah and Shan States==