A case was registered on Friday against DMK President M.K. Stalin and the party's Vellore Lok Sabha poll candidate D.M. Kathir Anand for holding a meeting without necessary permission, officials said.
The case was registered by police in Ambur in Vellore district.
The postponed Lok Sabha poll for the Vellore constituency is scheduled to be held on August 5 and the model code of conduct is in force there.
On Thursday, Stalin met leaders of the Muslim community at a marriage hall in Ambur without intimating and getting permission from the election officials.
The marriage hall where the meeting was held was also sealed for violation of model code of conduct.