M Arun Subramanian, representing Tirutanni in the Assembly, was arrested from his house in the town in neighbouring Tiruvallur District on a complaint that he had encroached on a public road in his constituency, police said.
He was produced before Judicial First Class Magistrate Gopinath who remanded him to judicial custody till August 1.
Alleging "political vendetta" behind the "sudden" arrest of his party MLA, Vijaykant in a statement accused police of foisting a "false case".
"The Jayalalithaa government was taking action against people they do not like. Now, DMDK is also their target," Vijaykant, a former ally of Jayalalithaa, said.
Since coming to power in May last year, the Jayalalithaa government had launched a crackdown on land grabbings and arrested several former DMK Ministers and MLAs, prompting the party to stage a fill the jail protest condemning the "political vendetta" unleashed on its leaders and workers.
DMDK was an ally of AIADMK in the last Assembly elections but the relationship between the two parties soured later leading to snapping of ties with Jayalalithaa saying she regretted having forged the alliance.
Police said Subramanian was arrested following a complaint by Municipal officials that he had encroached a public road near his land and built a compound wall six months ago blocking the thoroughfare to the public residing in the area.
A group of Irula community members, a Scheduled Tribe, had approached the Municipal authorities complaining that their access to road had been blocked by the MLA and sought action against him.
They also alleged that the MLA abused them by calling their caste name, police said, adding a case under SC/ST (Prevention of Atrocities) Act was also registered against him.
