Rottnest Island: Teen sunbather reportedly sexually assaulted by mystery man on New Year’s Eve

Police are looking for a mystery man after a teenage sunbather reported he was sexually assaulted at a popular beach on New Year’s Eve.

The woman had been lying on a beach towel on December 31 at Thomson Bay Beach on Rottnest Island off the coast of Perth, Western Australia.

Police say the young girl was attacked by an unidentified man on the busy beach between 10:15 am and 12:30 pm.

The woman had been lying on a beach towel in the sand at Thomson Bay Beach on Rottnest Island (pictured) off the coast of Perth, Western Australia, on New Year’s Eve

The teenager had been wearing a black bikini with a white sundress over it at the time of the alleged attack and was sitting north of the ferry dock.

Police say there were “numerous” people in the area at the time as crowds gathered to ring in the New Year on the scenic beach.

They would like to speak to anyone who remembers the woman or man acting suspiciously in the area on December 31.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000.

Police say there were “large” people in the area at the time as crowds gathered to ring in the New Year on the picturesque beach off the coast of Perth, Western Australia