Two groups of fishermen and tribals mostly drunk attacked each other last night following a brawl in the Chinakuria area here, they said.
Bombs were hurled during the clash and three tribals got injured in the process.
The tribals, however, gathered this morning and set the mud huts and private cars on fire and left three persons injured, police added.
They also gheraoed Niamatpur police outpost during the day but were later sent back to their homes, poice said.