Manjung police chief Hasbullah Abd Rahman said the woman was found by a tour guide at about 12.30pm.

“The victim was believed to have been snorkelling at Pulau Giam with other members of her family,” Hasbullah said.

A post-mortem will be conducted tomorrow. The case has been classified as sudden death.

Snorkelling is a water activity where a person swims on the surface face-down using a mask and a breathing tube called a snorkel to observe underwater life.