The bullet-ridden body of Saimung Ada, 50, was found in his home with a pistol in his hand.
According to a preliminary investigation, he was walking in front of his house when two gunmen hiding there fired at him.
The village head had earlier been attacked by a suspected insurgent. He fought back at that time and the gunman retreated.
He had publicly announced his stance, that he would work with government officials in response to the southern violence.