Udhayanidhi was taken into custody from his residence. As police escorted him out, he was seen smiling at supporters and the media.

Calling the arrest "a joke", the DMK leader said he would challenge the action legally. His party described the arrest as "political vendetta".

Kanimozhi calls arrest 'blatant cowardice'

DMK MP Kanimozhi strongly criticised the arrest in a post on X.

"If the government wants to personally take revenge on the Opposition Leader, Thiru @Udhaystalin, let it file a case. Let the court deliver its verdict. But, lacking the courage to confront the DMK as an opposition party, for the government to resort to such oppressive tactics is against the law," she wrote.

She further alleged that the arrest was aimed at preventing Udhayanidhi from attending the Tamil Nadu Assembly session beginning on Wednesday.

"Arresting the Opposition Leader in this way, solely to prevent him from participating in the Assembly session starting tomorrow, is blatant cowardice," she added.

TVK defends arrest

The Tamilaga Vettri Kazhagam (TVK) maintained that Udhayanidhi was arrested for allegedly insulting a woman.

The controversy stems from a speech delivered by Udhayanidhi during a protest over the Cauvery River water-sharing issue in Thanjavur.

According to reports, while responding to political slogans raised by supporters and targeting Chief Minister C. Joseph Vijay, Udhayanidhi allegedly made a remark that critics interpreted as a vulgar reference to actor Trisha Krishnan.

Complaint triggers political storm

TVK alleged that the comment was insulting and misogynistic and subsequently filed complaints with the police and the National Commission for Women (NCW).

The remarks quickly sparked a political controversy, with protests demanding action against the DMK leader.

However, DMK leaders defended Udhayanidhi, claiming his speech had been taken out of context and that political opponents had deliberately distorted his remarks.