A nine-year-old Israeli boy died Saturday after being stung by a box jellyfish in the surf off Koh Phangan island.
Poonsak Soponpathumrak, Koh Phangan district chief, reported the incident to governor Wichawut Jinto.
Mr Poonsak said the boy and his family were playing in water alongside Hat Rin beach at Moo 6 village in tambon Ban Tai about 5.30pm.
The father heard his son cry for help and ran to him. The boy had red marks on his right arm and legs and became dizzy. The father poured vinegar onto the stings and called Koh Phangan International Hospital. The boy died on the way to the hospital.
The district chief said signs written in three languages had been put up at Hat Rin beach warning tourists to enter the water only at designated areas. The areas are further surrounded by netting to protect swimmers from box jellyfish. Bottles of vinegar also have been provided at these spots to treat jellyfish stings.
Mr Poonsak said it appeared the boy had been playing in water outside the netted area.
Varawut Silpa-archa, minister for natural resources and the environment, said he had been briefed on the incident and expressed condolences to the family.