Thailand mourns the death of Khun Poom Jensen, the only son of Princess Ubolratana, who went missing when a gigantic wave hit his resort hotel at Khao Lak in Phangnga's Takua Pa district on Sunday.

Prime Minister Thaksin Shinawatra confirmed the sad news yesterday afternoon while inspecting losses in neighbouring Phuket province.

Mr Thaksin said the body of Khun Poom, 21, was found some 100 metres away from the La Flora hotel around 10am yesterday. His body was later taken by helicopter to Phuket Watchara Hospital.

His four bodyguards were safe with slight injuries, but two divers providing security for him while in the sea were still missing.

His Royal Highness Crown Prince Maha Vajiralongkorn flew a special plane to Phuket where Princess Ubolratana was staying to bring Khun Poom's body back to Bangkok at 7.20pm yesterday.

Khun Poom's body was then taken to Sahathai Pavilion in the Grand Palace for a royally-sponsored bathing rite, presided over by the Crown Prince. Also at the rite were Their Royal Highnesses Princess Maha Chakri Sirindhorn and Princess Chulabhorn and other Royal Family members. His Majesty the King granted a royal funeral urn for the body of his grandson.

Princess Ubolratana was seen weeping unceasingly as the rite went on.

Born in 1983, Khun Poom was the second of Princess Ubolratana's three children. He was a student at Kasetsart University's faculty of education, majoring in physical education. He loved swimming and outdoor sports including horse-riding and shooting.

Source: Agencies