Authorities arrested a motorboat driver on Wednesday for his alleged connection to the fatal shooting of a fisherman earlier this week, though soldiers and NGO workers thought to be responsible for the death are still on the lam.

A joint force of Pursat, Battambang and Kampong Thom Military Police arrested Yib Yin, 29, as he returned to his home in Ek Phnom district in Battambang on Wednesday night.

So Sovanndy, Pursat province Military Police deputy commander, said Yin confessed to driving two soldiers on his motorboat on a patrol where they later chased and fatally shot Ho Yang Toeng, a fisherman, in Pursat’s Kandieng district.

According to Sovanndy, Yin said he could not recall the soldiers’ names. Another motorboat, allegedly owned by Nguyen Yang Yoeung, also carried two NGO workers on the patrol.

Yin said he was unaware that the shooting would take place and, after fleeing the scene, hid in a patch of water hyacinths to get away from the other suspects, Sovanndy said.

Four suspects are still being sought for shooting Yang Toeng.

Kandieng District Police Chief Liv Se Em said he still could not confirm the identities of the NGO workers, but the National Police identified the NGO as 2 Thnou, or “2nd December”, which monitors illegal fishing. Yun Savat, head of 2 Thnou, said he hadn’t received any information on the case.