This is the breathtaking moment snorkelers swam with a massive stingray on a Thai island.

The divers found the manta ray swimming in the sea near Koh Rok island in Trang province on December 21.

They were surprised to find the sea animal in shallow waters as it usually swims deep in the ocean and is normally encountered by scuba divers.

Video shows the snorkelers gliding next to the giant marine animal, which reportedly had a wingspan of about 13 feet. It had a defect on its left fin that is believed to be from a shark bite.

The Guinness Book of World Records said the largest recorded manta ray wingspan is 30ft.

Trang sea province tour operator Phruek Ubonkerd said: ‘I have been snorkeling for 18 years, and this is the first time I’ve seen a manta ray swimming in shallow waters.

‘It’s the first time manta rays have been seen in such shallow waters near Koh Rok island. It was fortunate for both myself and the snorkelers to see it up close.’