GUWAHATI, India Thousands of people poured out into the streets defying a curfew in India's Manipur State on Saturday to protest a federal government decision to widen a cease-fire with separatist rebels to their state, police said.

"People violated the curfew which was imposed round the clock since Friday night and came out on the streets shouting slogans against the extension of cease-fire," a police officer at the control room in the state capital, Imphal, told Reuters by phone.

He said security forces had been put on maximum alert and military helicopters were carrying out aerial surveys.

Last month, 15 people were killed when police fired on protestors who torched the state assembly to protest against the widening of the truce with Naga rebels.

"People in Imphal are no longer afraid of the curfew and they are determined to intensify the agitation," Montu Ahanthem, a spokesman for the All Manipur Students Union (AMSU) told Reuters.

Authorities have ordered security forces to shoot curfew violators, but they are holding back fearing a bloody backlash.

Ahanthem said the students' union met with the junior home (interior) minister and made it clear they would not accept anything but withdrawal of the cease-fire from Manipur.

India extended the four-year-old truce with the National Socialist Council of Nagaland (NSCN) for another year, widening the areas to other Naga inhabitant areas in the region.

Analysts view the widening of the cease-fire to other areas beyond the remote Nagaland State as a step toward creation of a greater Nagaland carving out areas from northeastern states of Assam, Manipur and Arunachal Pradesh.