Inspector General of Police (Law and Order) L.R. Bishnoi said that the blast took place at Gandhi Murti Chowk near Doomdooma township in the district around 6.40 p.m.
"Twelve people were injured and they included three policemen," Bishnoi said while adding that among the injured, three had been referred to the Tinsukia civil hospital for treatment.
The hands of militants belonging to the anti-talk faction of the United Liberation Front of Asom(Ulfa) is suspected behind the blast, police said.
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