At least 13 people have died after an Indian navy speedboat lost control and crashed into a passenger ferry off the coast of Mumbai, a navy spokesman said.

Three navy personnel are among the dead, and more than 100 people have been rescued, Maharashtra state chief minister Devendra Fadnavis said.

Photos of the incident posted online show the speedboat circling before crashing into the ferry, which later sank.

The Indian navy said there had been an "engine malfunction". An investigation has been ordered to find out what caused the accident, according to local media reports.

The private ferry was making its way to the Elephanta Caves, a popular tourist spot, when it was hit by the speedboat.

"A cruise ship undergoing engine tests lost control and hit a passenger ferry," the navy said, saying it regretted the "terrible loss" of life.

Gautam Gupta told The Times of India that he first thought the speedboat had been doing stunts and was filming it from the deck when it crashed into the ferry.

Another passenger on board told the media that he had been swimming for 15 minutes before another boat came to the rescue.

Anil Bamane, who was one of the first rescuers at the scene, told the Hindustan Times newspaper that the air was filled with the sound of cries and screams for help.

Survivors told local media that ferry workers had not given any instructions after the crash, leaving passengers to scramble to safety on their own.

Prime Minister Narendra Modi has expressed his condolences to the families of the victims of the incident and termed the incident as sad.

He also announced 200,000 rupees ($2,352; £1,869) for the families of the deceased, as well as 50,000 rupees for those injured in the accident.

This is the second such incident in a month. The first occurred on November 22, when two people were reported missing after a submarine collided with a fishing trawler off the coast of Goa.