At least 28 people have died and 14 people are still missing after a tourist boat capsized in Vietnam during bad weather.

The incident took place in Ha Long Bay, a popular tourist destination in the north of the country.

Most of the passengers were reportedly Vietnamese families visiting from the capital Hanoi.

Heavy rain has been hindering the search for survivors, rescuers say, but so far 11 people have been pulled from the water alive.

The vessel, named Wonder Seas, was carrying 53 people when it capsized after encountering a sudden storm, a statement from the Vietnamese Border Guards and navy said.

A 14-year-old boy was rescued after four hours trapped in an air pocket in the upturned boat's hull, one official told the VNExpress news site.

Hospital director Le Ngoc Dung told the news site that a 10-year-old boy was also among those saved, and is currently in a stable condition at Bai Chay Hospital.

Of the 28 bodies so far recovered, eight were children, VNExpress reports.

Rescue efforts are set to continue into the night to find the dozens still missing.

Prime Minister Pham Minh Chinh sent his condolences to the families of the dead.

Ha Long Bay in Quang Ninh province is dotted with hundreds of tiny islets, attracting 4 million tourists in 2019, and is a Unesco World Heritage site.