Thirty-five people, mostly Russian tourists, were injured after their speedboat crashed in Chalong Bay in Phuket on Wednesday evening.
The accident occurred when the Thanathip Marine 555 was bringing 21 Russians, nine Kazakhstanis, two Chinese and one Ukrainian back from the Phi Phi islands to Chalong Bay at about 5.30pm. The boat driver, his assistant and a tour guide were also on board.
An initial investigation found that the boat driver might have dozed off.
The boat smashed into the channel marker located about 700 metres from the Chalong pier and sustained heavy damage.
About 10 people including the boat driver suffered broken limbs. Two people were reported to have serious injuries and others were slightly injured. They were taken to seven different hospitals on the island, according to local reports.