Two stuntmen who did not know how to swim drowned after jumping from a helicopter into a lake in southern India while shooting a film, police have said.

The crew were filming the climax of the movie on Monday when Raghav Uday and Anil Verma made the leap as part of an action sequence.

Police Superintendent Chandra Gupta said the two stuntmen did not know how to swim and were not wearing life vests. In addition, a motorboat which was supposed to rush to the scene and rescue them was found to be not working.

Video footage of the scene showed the pair landing in the water and thrashing around for a few seconds before disappearing from view. Local fishermen in small boats rowed to the middle of the lake but found no trace of them.

One of Kannada cinema's top actors, Duniya Vijay, also jumped into the water with the stuntmen, but managed to swim and was later rescued by a fisherman. The Kannada language is spoken in the southern Indian state of Karnataka, which has a thriving film industry.

Police have registered a case of criminal negligence against the film's director and producers, Mr Gupta said.