Navy, coast guard, air force and local police have launched a massive operation to rescue them.
Meanwhile, the Indian Navy has deployed five ships from Kochi while two are already on standby in Lakshadweep.
The authorities have opened relief camps at various places to accommodate people being evacuated from the affected areas including coastal areas.
FISHERMEN MISSING: A rough sea and pounding rains worsened fears in Thiruvananthapuram where families await the return of at least 100 fishermen who ventured out early on Thursday.
Responding to a request for assistance made by District Collector of Trivandrum, the Indian Navy dispatched its ships and aircrafts in a search and rescue operation.
Cyclone Ockhi intensifies to severe cyclonic storm, heavy rains batter coastal areas in Kerala, Tamil Nadu
Damage to paddy crops, banana, papaya trees and orchards has also been forecast while storm surge of about 1 meter above astronomical tides could very likely inundate low lying areas of Lakshadweep Islands from tonight, it warned.
In a series of tweets, Sitharaman further informed that six warships and two coast guard ships have been deployed along with additional air effort. A couple - Appu Nadar, 73, and Sumathi, 68 - also died due to the cyclone.
Schools and colleges in Chennai, Kanchipuram, Villupuram, Kanyakumari, Nellai, Theni, Dindigul, Madurai and Thoothukudihave been shut down and the authorities asked people to stay indoors in the wake of torrential rains and gusty winds. Rainfall of 7 cm to 11 cm is expected in the next 48 hours. Madhavan Rajeevan, secretary in the ministry, said the archipelago in the southern part of the Arabian Sea will start experiencing heavy rainfall and strong winds from Friday.