Dilip Paswan, 55, was shot dead near Bandal loco-shed last night by three men who came with their faces covered in a motorbike, Superintendent of Police Tanmoy Roychowdhury said.
Congress workers put up a blockade at Delhi Road at 7 AM today at Bandal in protest against the killing.
When a police team went there, the protesters started pelting stones at them and injured four policemen. The protestors also set a police jeep on fire, Roychowdhury said.
Police used batons to disperse the mob that also left five persons injured, he said.
The SP said efforts are on to arrest the killers of Paswan and the situation is now under control.