One of Burma’s biggest ethnic armies, the Karen National Liberation Army (KNLA), has claimed responsibility for Tuesday’s grenade attack on a hydropower plant in eastern Burma’s Karenni state.

The attack on the Thaukyegat plant, run by the Asian World Corporation, injured four workers. Saw Mae Ae Sein, commander of KNLA Brigade 2, said that an elite unit was yesterday sent to the dam site to carry out the attack.

The dam, currently under construction, has typically caused controversy and led to a militarisation of the surrounding area as the army looks to secure swathes of land for the project.

“There are concerns for the local’s survival; locals have been facing threats of shootings, oppression, forced labour, torture and forced relocation,” he said.

He added that the Karen army, which has been waging a 60-year civil war against the Burmese government, “had to strike because if we didn’t, the district would not survive.”

Troops from the 10,000-strong KNLA launched rockets and heavy weapons at the dam site, while the Burmese army returned fire. The fight last for about an hour, Saw Mae Ae Sein said.

“There were no casualties on our side but there were some on the government side, as well as some damage to their buildings.”

He said that the KNLA had not intended to injure civilians, “but militarily, it was unavoidable as they were at the site working for the government. Besides, it was likely that they were just people handpicked by the government to work at the site.”

Construction on Thaukyegat hydropower project begun in 2003. Saw Mae Ae Sein said that around 30 villages and nearly 100,000 people will be impacted by the dam.

Asia World Corporation came under attack earlier this month close to the site of another controversial dam in Burma’s northernmost Kachin state. Three bombs exploded inside the company’s compound close to the Myitsone dam, 18 miles north of the Kachin state capital, Myitkyina. Four Asia World employees were killed.