According to Tamil Nadu State Disaster Management Authority, as many as 76,290 people were evacuated from low lying areas and sheltered at over 300 relief centres in six districts including Nagapattinam, Pudukottai, Ramanathapuram and Tiruvarur.
A holiday has been declared for educational institutions in Nagapattinam here.
An India Meteorological Department (IMD) bulletin said, "severe cyclonic storm Gaja crossed Tamil Nadu and Puducherry coast between Nagapattinam and Vedaranniyam ...with wind speed of 100-110 kmph gusting up to 120 kmph, early Friday."
"Though the center of cyclone is over land, rear sector of eye wall is still over sea. It will take about an hour to move over land," the IMD bulletin issued at 3.15 AM said.
However, Deputy Director General of Meteorology S Balachandran told PTI, the cyclone will take another two hours to fully cross the coast.
During the cyclone's landfall, rains lashed Nagapattinam, Tiruvarur, and Thanjavur, uprooting trees in several regions, the details of which is expected later in the day.
Electricity supply was disconnected here and in several other coastal regions in view of the cyclone's landfall.
Four teams each of National Disaster Response Force personnel have been already deployed in Nagapattinam district while two teams of the state disaster response force in Cuddalore district, officials said Thursday.
The state disaster management authority had released an animated video aimed at creating awareness on the do's and don'ts during cyclone.
The government has announced helpline numbers 1070 (state-level) and 1077 (districts) for those who may need assistance.