A Russian man has been arrested and charged after throwing his 13-year-old son into the sea off Phangnga, resulting in the boy's death from severe injuries caused by a propeller.
The incident happened in Khura Buri district while tourists were present, with speedboat staff reporting it to police around 4pm on Wednesday.
The speedboat was carrying tourists back from Mu Ko Surin to Khura Buri pier, about 200 metres from the mainland.
The half-Thai, half-Russian boy, Lucas Bugorskiy, suffered critical injuries. He was sent to Kuraburi Chaipat Hospital but later died.
The boy's father, Artem Bugorskiy, was detained by the boat staff before being taken in for questioning by police.
According to the speedboat captain, there were 33 tourists on board – 17 Thais and 16 foreigners – and five crew members. The speedboat left Mu Ko Surin at about 3pm.
When the boat approached Mu Ko Ra–Ko Phra Thong, Mr Bugorskiy, 45, was seen leaving his seat, grabbing his son and throwing him into the water before jumping in after. Despite efforts to assist, the father refused help while floating in the sea.
After the captain manoeuvred the boat, a crew member retrieved the boy, who had sustained serious facial and head injuries from the boat's propeller.
Police have charged the Russian man with murder. He denied the charge.