Most of the Chinese tourists involved in the accident were individual travelers who had ordered a one-day local tour. They came from provinces such as Jiangsu, Zhejiang, Guangdong, Liaoning and Henan, according to the Chinese Ministry of Culture and Tourism.

The government of Haining, Zhejiang province, confirmed on Friday that atotal of 37 people, including employees and their family members, from a furniture company in the city were involved in the tragedy. As of Friday night, 18 of them were missing.

The city established a team on Friday to help the victims' relatives to deal with visa-related affairs.

Helicopters scanned the water on Friday as divers tried to reach the boat, which the Thai Navy said had sunk to 40 meters below the surface of the Andaman Sea, a few kilometers off the coast of Koh He, an islet known for its coral formations and popular with day-trippers from Phuket.

The three-deck Phoenix was carrying 105 passengers, including 93 Chinese tourists, as well as 12 Thai crew members and tour guides, when it hit trouble and capsized around 5:45 pm, sparking a rescue attempt that took place in the dark.

Another boat, the Senereta, also overturned off Phuket during the stormy conditions on Thursday, but all 42 on board, the majority of them Chinese tourists, were rescued.

The captain of the Phoenix told China Central Television that some garbage was caught in the drainage system, causing it to malfunction. The hull was unstable, and then several strong waves hit it. The ship began to tilt and finally capsized.

The boat, which went down about 7 km from shore, was properly registered and had not been overloaded, local police said.