A tourist boat carrying as many as 53 people has capsized in stormy weather, sparking a major rescue operation.
Rescuers have recovered at least 27 bodies from Vietnam's Halong Bay after the cruise vessel tipped over.
Some 48 tourists and five members of crew were believed to be on board when immense waves, strengthened by strong winds and heavy rain, caused the boat to lose its centre of balance.
Eight children are understood to be among the recovered bodies.
At time of writing, the nationalities of those involved is not yet known and emergency crews are understood to be continuing their search for survivors.
According to local press, the tourists on board included families with children, and were from the capital, Hanoi.
Rescuers have located 11 of the tourists alive as of 8.30pm local time today.
Two rescue craft and a number of smaller local vessels are understood to be working at the scene in a joint operation between police, navy, border guards. and port authorities.
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GETTY | Tourist boat carrying 53 capsizes in stormy weather - 27 bodies recoveredSpecialist divers have been conducting searches both inside the now-upside-down ship’s cabin and the surrounding waters in search of the missing victims.
Ha Long Bay is situated around 125 miles northeast of Hanoi and attracts tens of thousands of visitors every year.
Owing to the picturesque landscape surrounding the bay, boat tours are hugely popular among tourists.
The tourist boat was travelling in the bay just after midday before being hit by the storm at around 1.30pm.
REUTERS
|Rescuers at the scene of the capzised vessel
Quang Ninh Provincial People’s Committee said the vessel's GPS signal was lost just after 2pm.
The tragedy comes as long range weather forecasts predict Storm Wipha, the third typhoon to hit the South China Sea this year, is projected to make landfall along Vietnam's northern coast early next week.
Air travel to the region was also affected with Noi Bai Airport confirming nine arriving flights were diverted to other airports.
Three departing flights were also temporarily grounded on Saturday.
The vessel has been named as the Wonder Seas, a statement from the Vietnamese Border Guards and Navy said.
One eyewitness observed the sky darkening around 2pm local time.
He reported there were "hailstones as big as toes with torrential rain, thunderstorm and lightning".
Local news site VNExpress reported one of the rescued tourists was a 14-year-old boy.
Rescuers found the boy in an air pocket in the upturned hull, having been trapped and treading water for four hours.
Hospital director Le Ngoc Dung said a 10-year-old boy who was another among those saved, is currently in a stable condition at Bai Chay Hospital.
Prime Minister Pham Minh Chinh has sent his condolences to the families of the dead.
Authorities have confirmed an investigation will be launched into the cause of the incident and "strictly handle violations".