Troops from the Arakan Liberation Army (ALA) based out of the western Burmese state are said to have been involved in an ambush on two Burmese army columns last week passing through territory claimed by Karen rebels.

One Burmese soldier died in the attack, according to the Democratic Karen Buddhist Army (DKBA), which was joined by the All Burma Students’ Democratic Front (ABSDF) and Arakanese rebels.

Ties between Karen and Arakanese ethnic armies stretch back several decades to 1968, when the ALA’s founding was aided by the Karen National Union, which over the subsequent decades trained its troops. But the involvement of Arakanese rebels in the recent fighting in Karen state has been kept quiet.

The ambush took place on 15 October, according to Saw Three Two, a captain in the DKBA. “We launched the attack jointly with the students’ army [ABSDF] and the Arakanese group. We didn’t suffer any casualty. We stay inside our own territory and we have to shoot [Burmese troops] when they enter ours.”

The fighting comes despite a pledge by the government to begin peace talks with a number of ethnic armies in the country’s border regions. Saw Three Two said that rather than President Thein Sein, the problem may lie with the army chief.

“General Min Aung Hlaing is continuing with the offenses and we don’t know who to trust so we might as well not trust them at all,” he said. “We decided not to accept their proposal – they said they would withdraw their forces on 15 October but instead they sent in more troops.”

Several armed groups, including the Karen National Liberation Army (KNLA) and the Shan State Army (SSA), put their names to the creation of a United Nationalities Federal Council (UNFC), effectively an attempt to build a cohesive ethnic front against the Burmese military.

Although the ALA is not part of the alliance, its forces are deployed along the Thai-Burma border and the length of the Arakan state border with Bangladesh and India.