A body found off Florida's coast is believed to be that of missing Canadian filmmaker Rob Stewart.

A search had been underway for the director of the award-winning documentary Sharkwater since he disappeared during a scuba dive on Tuesday.

The US coast guard said the body was found around 300ft from where the 37-year-old went missing off the Florida Keys.

Identification by the local medical examiner was pending, a spokesman said.

In a Facebook post, Stewart's sister, Alexandra wrote that her brother had been found "peacefully in the ocean".

"Rob has been found, peacefully in the ocean. There are no words,"

"We are so deeply grateful to everyone who helped search, and happy that Rob passed while doing what he loved," Ms Stewart wrote.

The film-maker, wildlife photographer, conservationist and writer is a self-confessed "shark lover" and the 2007 documentary argued that the creatures are misunderstood.

It was being followed up by Sharkwater 2, which is expected to be released later this year.