Angry mob torched three buses and a truck after a truck run over and killed a 12-year-old student at Shibpur in Howrah district Tuesday morning.
The incident occurred near Shalimar bridge when the boy, who was coming from a nearby market, was crushed under the wheels of the truck, the police said.
Infuriated local people then torched the truck and, with it, three buses. It took two fire tenders nearly two hours to douse the fire.
Top police officials including Superintendent of Police HK Kusumakar, Additional SP (Town) Sukesh Jain and DSP (South) Ashok Ray rushed to the spot and police lathicharged to disperse the mob.
Local people alleged accidents take place regularly in the area as unauthorised parking has made the road narrow.
"We will remove all the unauthorised vehicles from the road within 24 hours," Kusumakar assured the local people.