The two Garo chiefs, Prakash Marak, Nokma of Khongtokpara, and Nikme D Sangma, a woman Nokma of Magupara, were arrested yesterday, they said.
The situation in Dalu area is under control, but still tense so curfew has not been lifted, they said after district Deputy Commissioner Pravin Bakshi toured the area to take stock of the situation.
Attempts to create tension in the area persists and additional security forces have been deployed to prevent any untoward incident, police said.
Curfew was clamped in areas under Dalu Police Station on June 9 following a land dispute between two major Garo tribal clans leading to the death of a woman and damage to property.