Myanmar's junta said Tuesday it would heed regional pleas to stop violence only when the country "returns to stability", as fresh fighting erupted with a major ethnic rebel group along its eastern border.

The nation has been in turmoil since the military ousted civilian leader Aung San Suu Kyi in a February 1 coup, triggering a protest movement that security forces have met with deadly crackdowns.

The violence -- in which more than 750 people have been killed by security forces, according to a local monitoring group -- has raised alarm among regional neighbours.

Fighters from the Karen National Union (pictured) have clashed with the military in their territory along Myanmar's eastern border for weeks
Fighters from the Karen National Union (pictured) have clashed with the military in their territory along Myanmar's eastern border for weeks KAREN NATIONAL UNION (KNU) / Handout

Junta leader Min Aung Hlaing attended a weekend meeting on the crisis with the leaders of the 10-country Association of Southeast Asian Nations (ASEAN) -- his first overseas trip since he seized power.

The leaders issued a "five-point consensus" statement that called for the "immediate cessation of violence" and a visit to Myanmar by a regional special envoy.

On Tuesday, Myanmar's State Administrative Council -- as the junta dubs itself -- said it would consider the "constructive suggestions made by ASEAN leaders when the situation returns to stability in the country".

The Karen National Union insurgent group said they had captured and burned down a Myanmar military base near the Thai border
The Karen National Union insurgent group said they had captured and burned down a Myanmar military base near the Thai border KAWTHOOLEI TODAY / Handout

The statement also said its neighbours' suggestions would be "positively considered if it (ASEAN) would facilitate the implementation" of the junta's five-step roadmap.

Junta spokesman Zaw Min Tun told AFP the regime was "satisfied" with the trip, saying it had been able to explain the "real situation" to ASEAN leaders.

But ASEAN is not known for its diplomatic clout and observers have questioned how effectively it can influence events in the country.

Smoke rises from a Myanmar military base, as seen from Mae Sam Laep in Thailand, after the base was captured by the Karen National Union
Smoke rises from a Myanmar military base, as seen from Mae Sam Laep in Thailand, after the base was captured by the Karen National Union KAWTHOOLEI TODAY / Handout

The former US ambassador to Myanmar, Scot Marciel, warned that the military's response to the Jakarta summit showed signs of backsliding already.

"ASEAN cannot dither here, as the junta moves to walk back even the limited agreement reached Saturday," Marciel said in a tweet.

"There should be urgent follow-up, and costs imposed on the junta for delay."

The coffin of a teashop owner shot dead during protests in Mandalay
The coffin of a teashop owner shot dead during protests in Mandalay AFP / STR

Cities, rural areas, remote mountainous regions and even the rebel-ruled territories along Myanmar's borders have erupted in dissent, protesting near-daily for the military to step down.

Protesters make the three-finger salute of resistance during a demonstration against the junta in Mandalay
Protesters make the three-finger salute of resistance during a demonstration against the junta in Mandalay FACEBOOK / Handout

One of the most prominent rebel groups, the Karen National Union (KNU), has admitted sheltering at least 2,000 anti-coup dissidents who fled urban centres of unrest.

In the early hours of Tuesday, soldiers from the KNU's Fifth Brigade attacked and razed a military base in eastern Karen state near the Salween river -- which demarcates part of the border shared with Thailand.

The attack was confirmed by both the KNU and junta spokesman Zaw Min Tun, who vowed to "take action".

By around noon, the military retaliated by launching air strikes north of the base, according to Sithichai Jindaluang, the Thai governor of bordering Mae Hong Son province.

"Thailand does not support either side but concentrates on ensuring the safety of Thai nationals," he said. His province has also devised a "refugees management plan".

Sithichai added that a stateless woman who lives in Mae Sam Laep was shot in the leg, caught in the crossfire. She was treated at hospital and in a stable condition, he said.

Last month, after the KNU overran a military base in the same region, the junta responded with multiple air strikes at night.

Since then, fighting between the two sides has displaced some 24,000 civilians, including more than 2,000 who crossed the river to seek refuge in Thailand before they were pushed back by border authorities.

Villagers on the Thai side of the border had already fled their homes, said Hkara, an ethnic Karen longtime resident, adding that she heard explosions and gunfire from inside Myanmar around 5 am.

"Nobody dares to stay," she said.

Across Myanmar, security forces have killed more than 750 civilians since February 1, according to the Assistance Association for Political Prisoners, a local monitoring group tracking the death toll.

But the junta -- which called the AAPP an "illegal organisation" -- has registered a far lower number while blaming "rioters".

Senior General Min Aung Hlaing's weekend trip to Jakarta has done little to halt the use of lethal force by soldiers and police -- with a teashop owner shot dead during protests in Mandalay two days after the get-together.

Tuesday also saw tensions in eastern Loikaw city, when security forces tried to remove barricades and opened fire on residents who tried to stop them -- killing one.

And in Mandalay, Nay Myo Linn, editor in chief of independent media outlet Voice of Myanmar, was detained, according to his wife Zarni Mann and one of his colleagues.