A late-night crackdown by the police and paramilitary forces on anti-mega dam protesters in Lakhimpur district triggered raging protests at several places in Assam on Monday.

The police arrested more than 200 protesters, who since December 16 had been blocking vehicles transporting equipment and construction materials, through National Highway 52, for the NHPC's 2,000-MW Lower Subonsiri hydroelectric project at Gerukamukh in Arunachal Pradesh.