Dey was elected as district secretary of the Trinamool in 2008 but the party dismissed him from the post months later following reports of his alleged involvement in various anti-social activities.
Jaiprakash Khaitan, the owner of the nursing home, said Dey had earlier also threatened many people, but after Dr Debangshi was selected for the post of secretary of the Trinamool-backed association, rivalry between the duo started to aggravate.
A complaint was lodged with the police on Sunday afternoon. Superintendent of Police (Birbhum) Murlidhar said they are investigating the matter.
Dey could not be contacted. Trinamool MP from Birbhum Satabdi Roy admitted factionalism in the party’s district unit. She said Dey was a criminal and accused him of “always trying to hatch a conspiracy” against the faction led by MLA Swapan Ghosh.