Four persons were reportedly missing after a fibre fishing boat that set off from Malippuram capsized near Munambam on Thursday evening.
While three persons were rescued, four were still missing.
The Indian Coast Guard was pressed into service for the rescue operations and the search is on to find the missing fishermen after the boat overturned at night.
Meanwhile, one of the rescued fishermen told the media that they held on to water cans for hours before a fishing boat rescued them.