A man who survived the capsizing of a tour boat in Ha Long Bay, Vietnam, has described his escape from the overturned vessel, saying he "saw a streak of light and followed it to swim out".
At least 35 people were killed in the accident and a search is continuing for four who are still missing, according to Vietnamese state media.
Authorities said earlier reports of 38 dead and five missing were incorrect.
The Wonder Sea embarked on Saturday for a three-hour excursion in Ha Long Bay, a popular tourist destination, carrying 46 passengers and three crew.
But a storm quickly covered the sky, bringing high winds and pouring rain, survivor Dang Anh Tuan told The Associated Press.
Rescue workers saved 11 people, some of whom had clung to the capsized boat's hull for hours. Source: AP / QDND
"It rained for about 15 minutes, and then the boat started to shake vigorously, tables and chairs were jostled around and seconds later the boat overturned," the 36-year-old fire extinguisher salesman said.
"Water gushed in and I lost all orientation.
"I tried to breathe. But more water came in. I took a deep breath, got rid of my life vest and dove down.
"I saw a streak of light and followed it to swim out, escaping the boat, and then I climbed on the overturned boat to look for help."
Tuan and three others survived by clinging to the capsized boat and its propellers, waiting another two hours until the rain stopped and rescuers arrived.
Ha Long Bay in Vietnam attracts tens of thousands of visitors each year. Source: PA / Nguyen Van Hai-Barbier Jean Pierre
Police and other officials were seen working on the boat.
Rescue workers recovered 11 survivors, but one later died in hospital due to his injuries, VNExpress newspaper said.
The boat turned upside down because of strong winds, the newspaper said.
A 14-year-old boy was rescued after four hours of being trapped in the overturned hull.
The newspaper said most of the passengers were tourists from Hanoi, including about 20 children.
Tuan was on a holiday with 11 university friends, only three of whom survived.
Tuan has only minor cuts, but one of his friends suffered multiple head injuries and the other's tendons were cut by broken glass as he escaped the boat through a window.
The other nine members of the group were killed, including one who was travelling with his wife and three-year-old son.
A tropical storm is also moving toward the area.
A national weather forecast said Storm Wipha was expected to hit Vietnam's northern region next week, including Ha Long Bay's coast.
