A Swiss woman, 57, was found dead among rocks at a Phuket waterfall on Thursday afternoon. She was believed to have been raped and murdered.

A local man told police after finding the body at about 1.30pm.

Police found the body of a woman lying face down in the water among rocks, about one kilometre from the entrance of the Ao Yon waterfall. Her body was covered with a black sheet, with her feet above the water.

Police estimated she had died at least three days ago. They also found what appeared to be her passport.

Near the body, police found clothing and a mobile phone.

Police said the woman had arrived at Phuket airport on July 13 under the Phuket Sandbox reopening scheme.

An immigration police source said the woman had arrived alone from Singapore and stayed at Dusit Thani Laguna Hotel from July 13 to 27 before moving to The Mooring Resort Hotel. A witness saw her walking out of the hotel towards a beach at about 2pm on Tuesday.

She had visited Phuket in 2019 and later left Chiang Mai province for Singapore.

The body was sent for an autopsy. Police were investigating.