Workers of two rival trade unions clashed at Meghna more in Jagaddal area in which bombs were hurled killing two TMC workers and injuring one worker, the sources said.
The injured worker who suffered bomb splinter injuries has been rushed to Naihati State General Hospital, the sources said.
When the police was rushing the injured worker and the bodies to the Naihati State General Hospital, a crowd attacked the policemen, they said.
Senior police officers have rushed to the spot as tension prevailed in the area.