The CRPF was called in and the police used water canons to disperse the clashing groups during a 12-hour Barak Valley bandh following which the indefinite curfew was imposed, police sources said.
Clashes also broke out at Nilambazaar in Karimganj district leaving three persons injured, the sources said.
Altogether 330 persons were arrested in Cachar, Karimganj and Hailakandi districts, they said.
The bandh was against alleged harassment in the name of search operations to arrest those responsible for the assault on Congress MLA Rumi Nath and her second husband Jacky Zakir last Friday at a hotel in Karimganj.
Action was also demanded against Nath for bigamy as she had married Zakir without divorcing her first husband Rakesh Kumar Singh.
The assault on Nath and Zakir has, however, been condemned by many quarters.
The bandh was called by the Hindu Jagran Manch and was supported by the BJP, the Vishwa Hindu Parishad, Hindu Milan Manch, Bharatiya Janata Yuva Morcha and some other outfits.