Police said two motorcycle-riding assailants shot at Lafikul in Basugaon area in Kokrajhar district around 3.30 pm from a close range. He was immediately taken to a hospital, where he was declared brought dead. Two persons have been detained so far in this connection.
Later in the day, ABMSU supporters blocked roads by burning tyres and shouted slogans in Basugaon and other adjoining areas, protesting the killing.
Leader of Opposition in the Assam assembly Debabrata Saikia condemned the student leader's murder and termed it "a failure on the part of the state government to maintain law and order".
"Late Islam boldly raised his voice against the injustice meted out to people living in Bodoland Territorial Areas Districts by the government as well as by a section of people," said Mr Saikia while demanding action against the assailants.
He asked Director General of Police Mukesh Sahay to rush to Kokrajhar to review the situation and initiate investigations to nab the killers within 24 hours.
Mr Sonowal also asked the Deputy Commissioner of Kokrajhar to maintain vigil on the situation, and to ensure peace and order in the district.
The Chief Minister also asked Special DGP Kula Saika to rush to Udalguri and assess the situation.
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