Myanmar’s junta captured a Civilian Defense and Security Organization of Myaung camp in Myaung Township, Sagaing Region, on Thursday.
Around 90 troops from the Nat Yay Kan village camp in neighboring Chaung-U Township attempted to occupy the outpost, according to the resistance group.
During about seven hours of fighting other resistance groups arrived to help the defense.
The resistance forces retreated from the camp when a Russian-made Mi-35 helicopter attacked for an hour, Ko Nway Oo of the organization told The Irrawaddy on Friday.
After a brief occupation, the junta troops retreated to Chaung-U overnight. Ko Nway Oo estimated that around 30 junta troops were killed or injured in the attack.
The Irrawaddy could not independently verify the reports.
Four resistance fighters were injured, said Ko Nway Oo.
In retaliation, resistance groups conducted drone strikes on the junta’s Chaung-U base on Friday, although no details about the damage are known.
Ko Nway Oo said the Nat Yay Kan troops were responsible for the massacre of 32 villagers during their raid on nearby Lethtoketaw village in Myinmu Township this month.
On May 17, around 300 junta troops destroyed a Yesagyo Revolution base in Yesagyo Township in Magwe Township, adjacent to Myaung Township, the group said.
Motorcycles and other vehicles were destroyed, the group said.
The troops also shot dead seven civilian detainees after using them as guides to reach the Yesagyo Revolution camp, the group told the media.