The banned National Democratic Front of Bodoland (NDFB) militants struck terror in lower Assam killing 13 people and injuring 23 in separate incidents on Saturday, while one of its cadres was shot dead by security forces.

A group of five heavily armed NDFB guerillas stormed the Makrijhora weekly market on National Highway 31 in Dhubri district at around 5.30 pm and opened fire killing 11 people on the spot and seriously injured four others.

Dhubri Superintendent of Police Dr L R Bishnoi said the ultras stormed the busy weekly market, which is on the borders of a dense jungle, when it was thronged by people. They opened fire from automatic weapons killing 11 people and fled into the jungle.

Four others who were injured have been admitted to Dhubri Civil Hospital, he said.

In a simultaneous attack, a separate group of NDFB militants fired on a truck travelling from Guwahati to Bihar and injured three people inside the vehicle, official sources said.

In another incident in neighbouring Chirang district on the Indo-Bhutan boder, the ultras exploded a bomb at Santipur Bazaar under Runikhata border outpost, killing two persons, the sources said.

The 16 injured were admitted to hospital at Dhaligaon.

Last night the security forces shot dead one NDFB ultra in Kokrajhar district, they added.