(Reuters) -- Fighting raged at Myanmar's eastern frontier with Thailand on Saturday, witnesses, media and Thailand's government said, forcing about 200 civilians to flee as rebels pressed to flush out junta troops holed up for days at a bridge border crossing.
Resistance fighters and ethnic minority rebels seized the key trading town of Myawaddy on the Myanmar side of the frontier on April 11, dealing a big blow to a well-equipped military that is struggling to govern and is now facing a critical test of its battlefield credibility.
Three witnesses on the Thai and Myanmar sides of the border said they heard explosions and heavy machine gun fire near a strategic bridge late on Friday and into early Saturday.
Several Thai media outlets said about 200 people had crossed the border to seek temporary refuge in Thailand.
Thai broadcaster NBT tweeted on X that resistance forces used 40-millimeter machine guns and dropped 20 bombs from drones to target an estimated 200 junta soldiers who retreated from a coordinated rebel assault on Myawaddy and army posts that began on April 5.
Reuters could not immediately verify the reports, and a Myanmar junta spokesperson could not immediately be reached for comment.
Thai Prime Minister Srettha Thavisin said he was closely monitoring the unrest and his country was ready to provide humanitarian assistance if necessary.
"I do not desire to see any such clashes have any impact on the territorial integrity of Thailand, and we are ready to protect our borders and the safety of our people," he said on X. He made no mention of refugees.
Myanmar's military is facing its biggest challenge since first taking control of the former British colony in 1962, caught up in multiple, low-intensity conflicts and grappling to stabilize an economy that has crumbled since a 2021 coup against Nobel laureate Aung San Suu Kyi's government.
The country is locked in a civil war between the military on one side and, on the other, a loose alliance of established ethnic minority armies and a resistance movement born out of the junta's bloody crackdown on anti-coup protests.
The capture of Myawaddy and surrounding army outposts was a significant setback for a junta that has been squeezed by Western sanctions, with the town a key tax revenue source and conduit for more than $1 billion of annual border trade.
The Khaosod newspaper tweeted a video of Myanmar civilians, many of them women and children, being marshaled by Thai soldiers at an entry point to Thailand.
Thailand on Friday said no refugees had entered the country and it was discussing with aid agencies about increasing humanitarian relief to civilians on the Myanmar side.
