Around 25 per cent votes were cast in the first three hours of polling in Tripura on Thursday, Chief Electoral Officer K V Satyanarayan said.

The All Tripura Tiger Force has called for a poll boycott and there is tight security all over the state.

Satyanarayan, however said the "people are exercising their franchise without fear."

A group of ATTF ultras opened fire at Dhanaipara school booth in West Tripura district at 0830 IST, but there were no casualtie, police sources said.