CPI(M) sources here today said that Dey was expelled for having personal links with chitfund scam-tainted Saradha group without the knowledge of the party.
Dey was a member of the party from Khardah in North 24 Parganas district.
Dey was summoned by Bidhannagar police on Wednesday for interrogation in connection with the Saradha chitfund scam.