Tongan police say they will issue warnings for the waters where a US Peace Corps Volunteer died in a shark attack.
24 year old Tessa Horan had been swimming in deep waters about 60 metres from the shore at Tu'anuku village in the Vava'u group of islands.
The Deputy Police Commander, Lola Koloamatangi, says police have no explanation as to why the shark attacked the volunteer.
"This is the first incidence of this nature to happen in the Vava'u waters. The police are giving out a notice for people to be aware that the area is dangerous for swimming."
Mrs Koloamatangi says police will work with the marine department to improve safety but a marine department spokesperson says they have not received a formal police request yet.