Ranganathan was arrested here this morning based on a complaint, police said. DMK senior leader Veerapandi S Arumugam, Chepauk constituency MLA J Anbazhagan and close aides of Union Minister M K Alagiri, have already been arrested in connection with land grab charges.
Turning up the heat on DMK, the state government had formed a special cell to exclusively deal with the land grabbing cases.
Party President M Karunanidhi has termed the arrests as ''vendetta politics'' but Chief Minister Jayalalithaa denied the charge, saying the special police cells were acting on "genuine" complaints by "affected" persons with no political link.
The DMK had staged a state-wide protest yesterday, saying police were "foisting" such cases against its members.
The crackdown is the result of an electoral promise by Jayalalithaa during the assembly elections that she would take action against land grabbing during DMK rule.