Political leaders cutting across party lines and DMK cadre today made a beeline for the residence of M Karunanidhi, who is being treated for fever due to urinary tract infection.

Prime Minister Narendra Modi wished the 94-year-old DMK chief a quick recovery.

"Spoke to Thiru @mkstalin and Kanimozhi Ji. Enquired about the health of Kalaignar Karunanidhi Ji and offered any assistance required. I pray for his quick recovery and good health. @kalaignar89 (sic)," he tweeted.

Security has been beefed up at Karunanidhi's Gopalapuram residence as DMK cadre kept pouring in there.

Kauvery Hospital, which providing medical treatment for the nonagenarian leader, said in a bulletin last night, "There has been a slight decline in the health of DMK president M Karunanidhi due to age-related ailments."

MDMK chief Vaiko, Tamil Nadu BJP chief Tamilisai Soundararajan, and Tamizhaga Vazhvurimai Katchi leader Velmurugan visited the residence of Karunanidhi and enquired about his health from his family members and the DMK working president M K Stalin.

Visitors are not allowed to meet the ailing leader.

After visiting Karunanidhi's residence, Vaiko told reporters, "Such fever after a tracheostomy procedure is usual. Stalin told me that he is fine. I am confident that he will bounce back with the same magnetic voice."

Karunanidhi has been not keeping well since October 2016, and some days ago he had undergone a procedure to change his tracheostomy tube, provided to help in breathing.

Stalin had on Wednesday said Karunanidhi was suffering from fever and doctors were providing medication, as he assured people that there was nothing to worry about the nonagenarian leader's health.