Koh Phi Phi Police reported that the woman was visiting the Pha Daeng diving area in Moo 7, Ao Nang Subdistrict, when the incident occurred at about 1pm.
The woman had travelled from Phuket earlier in the morning by speedboat, arriving at Phi Phi between 9am and 9:45am. The tour group later moved to the Pha Daeng site, where tourists were swimming.
According to the initial police report, the woman was attempting to get out of the water when she was struck by a wave and began choking. She appeared exhausted and lost consciousness about 15 minutes later. She was brought ashore and transferred to Koh Phi Phi Hospital, where medical staff later confirmed her death.
Pol Lt Apilak Suwanlikhit, Deputy Inspector for Investigations at Koh Phi Phi Police Station, was notified of the fatality at 2:42pm. Officers investigated the scene and gathered statements from tour operators and witnesses.
Police say the cause of death remains under investigation pending the results of a medical examination of the woman’s body.