A joint team of police and the army on Thursday shot dead a United Liberation Front of Assam militant, Pranjal Deka alias Biju Sarania who was alleged prime suspect behind the January 1 serial blasts in Guwahati, in an encounter at Halikuchi in Rangiya sub-division of Kamrup district.

A top official in Assam Police informed that two ULFA militants were engaged in an encounter by a joint team of the army and police at Halikuchi on the bank of a river in Rangiya sub-division of Kamrup district on Thursday afternoon.

Pranjal Deka was killed in the exchange of fire while the other militant managed to flee by crossing the river.

The January 1 serial blasts in Guwahati had claimed the lives of five persons and injured 50 others.

Police had earlier released the photograph of Pranjal Deka, branding him as the prime accused in the serial blasts.

Police said Pranjal planted one of the three bombs besides being the mastermind of the serial blasts. Assam Police have so far arrested about 18 persons in connection with the blasts. He was a member of 709 battalion of the banned ULFA.

The three bombs on New Year's Day were triggered at Birubari, Bhangagarh and Bhootnath areas in the city.