The incident took place at Aathiabari Tiniali under Serfanguri police station. Commissioner (Home) G.D. Tripathy said that while five people were killed on the spot, two others were injured in the attack. Two more people were missing after the incident, he said.
Police sources said that a group of armed militants stopped the bus, which was travelling from Bongaigaon to Kokrajhar, at Aathiabari Tiniali and forced at least 10 people to get down and opened fire at them.
Top police officials rushed to the spot and launched an operation against the militants.