NAYPYIDAW  -  The military regime which seized power in Myanmar three years ago has suffered another big defeat, this time on the eastern border with Thailand. Troops had suffered weeks of attacks by ethnic Karen insurgents, allied with other anti-coup forces.

Hundreds of troops guarding the vital border town of Myawad­dy have now agreed to surren­der. Most of Myanmar’s overland trade with Thailand passes through Myawaddy. On Friday, the Karen National Union announced that it had accepted the surrender of a battalion based in the town of Thanganyinaung, about 10km (6.2 miles) west of Myawaddy.

It posted a video of its jubilant fighters showing off a substantial arsenal of weapons they had cap­tured. Over the weekend, the Kar­en forces have been negotiating with the last remaining battalion inside Myawaddy, which has ap­parently agreed to surrender.

This is a serious setback for the military junta, which in re­cent months has also been driv­en out of large areas along the Chinese border in Shan State, and in Rakhine State near the border with Bangladesh. Thou­sands of soldiers have already ei­ther been killed, or have surren­dered or defected to the opposition, forcing the military to impose con­scription on the popula­tion to try to make up the losses.

Myanmar’s army is losing - and facing fire from a militant monk The Karen National Union has been fight­ing for self-rule for the ethnic Karen people since Myanmar’s in­dependence in 1948. However it suffered a series of defeats by government forces in the 1990s, and after 2015 had been part of a national ceasefire.

The 2021 coup changed that, with the KNU announcing that the overthrow of the elected govern­ment led by Aung San Suu Kyi had invalidated the ceasefire. Because it is relatively close to Yangon, the largest city in Myanmar, and of­fers the best route to the Thai bor­der, Karen State was a favoured destination for dissidents fleeing the brutal military suppression of protests after the coup.

The KNU has helped train many volunteer fighters from the cities, who have joined it in renewed at­tacks on military positions.

The KNU has also been try­ing to co-ordinate its operations with those of other big insurgent groups like the Karenni Nationali­ties Defence Force to the north of Karen State, and the Kachin Inde­pendence Army in the far north of the country. The balance of power in Karen State has recently shifted in favour of the opposition, as a powerful militia based on the Thai border, funded by scam cen­tres and which had been back­ing the military junta, switched sides earlier this year. Over­stretched by fighting in so many other parts of Myan­mar, the mili­tary has also been unable to reinforce its po­sitions in Karen State, and it lost control of the main roads to the border. The jun­ta has responded to these losses by launching more air strikes on the areas now controlled by the insurgents. Thousands of non-combatants have already lost their homes to the conflict in Karen, and many more are now reported to be moving towards the Thai bor­der in anticipation of continued air strikes in the days ahead.