Thirteen Indian students drowned on Monday after they went swimming in the sea off the country's west coast, police said.

The tragedy happened at Murud beach, around 140 kilometres (90 miles) south of Mumbai, in the Raigad district of Maharashtra state, said assistant inspector of police Arvind Patil.

"The victims were all aged between 19 and 23," he told AFP, adding that 10 women and three men died.