About 150 fishermen, who put out to sea from various southern districts, were rescued, Thiruvananthapuram District Commissioner K Vasuki said, adding that efforts were on to bring the rest of the stranded fishermen to the shore.
"There is no need to panic," she said.
The rescued fishermen included those who were saved by a Japanese cargo vessel.
The vessel has rescued 60 fishermen from mid-sea. They are being brought to the Vizhinjam coast near here, she said.
Many rescued fishermen have been admitted to the medical college and general hospitals since they were weak after being in the sea for the last 48 hours, the official said.
Yesterday, the state reported four rain-related deaths, including that of an elderly couple who were electrocuted when they came into contact with a snapped live wire in front of their house at Kattakada near Thiruvananthapuram.
Rescue operations in full swing.
Even though the sea continued to be rough, rescue operations are going on in full swing.
The Navy, Coast Guard and Air Force are engaged in rescue operations with their ships, aircraft and helicopters.
Besides engaging divers, the Indian Navy has deployed two aircraft and an advanced light helicopter (ALH).
The Indian Navy is putting in "maximum effort" to rescue fishermen from the sea which is very rough under the influence of Cyclone Ockhi, Vice Admiral A R Karve, Flag Officer Commanding-in-Chief, Southern Naval Command, told reporters on board the INS Tir at the naval base in Kochi.
Chief Minister Pinarayi Vijayan said the state has asked the defence ministry to deploy more aircraft for rescue operations as the cyclonic storm moving towards Lakshadweep.
Top Navy officials said they deployed two ships to the Lakshadweep Islands for carrying out rescue and rehabilitation operations in the island.
In Lakshadweep, orders have been issued to evacuate people from low-lying areas in Kalpeni, Minicoy, Kavratti, Agatti, Androth, Kadamath and Amini islands, official sources said.
People are being shifted to schools, they said.
Five boats anchored at a jetty in Kalpeni were damaged in heavy rains, coupled with strong winds.
Anxious relatives of the missing fishermen, including women, today blocked traffic and raised slogans in Kollam and Thiruvanathapuram, protesting the delay in their rescue.
In Thiruvananthapuram, fishermen and women blocked the national highway braving heavy rains.
Former chief minister Oommen Chandy, BJP state president Kummanam Rajasekharan visited a fishing hamlet in Poonthura near here, from where a large number of fishermen, who put out to sea, were yet to return.
As per the latest MeT bulletin, the system is very likely to intensify further during the next 24 hours.
"It is very likely to continue to move west- northwestwards across Lakshadweep islands during the next 24 hours and then move north-northeastwards during the subsequent 48 hours," it added.