But the same reptiles were breeding rapidly in captivity. Orissa's Bhitarkanika sanctuary has more than 1,400 crocodiles now.

"The swelling number of released crocodiles in the wild is working as a deterrent and keeping people away from the mangrove as villagers are more cautious before venturing into the forests," said Rathin Banerjee, a senior wildlife official.

Wildlife sanctuaries in the region are threatened by poachers and villagers foraging for wood and forest produce.

But large crocodiles leaping out of the water to attack prey or capsize boats and canoes were proving to be a good weapon, said Banerjee, a crocodile breeding expert.

Last year, a 23 foot (7 metres) estuarine crocodile in Bhitarkanika entered the Guinness Book of World Records as the world's largest.

Three other estuarine crocodiles at the sanctuary, all measuring more than 19 ft, have also found a mention on the Guinness Web site.