Divers searched beneath the waves for missing passengers and crew after a sightseeing ship capsized in a squall in Halong Bay, a popular tourist destination in Vietnam, on Saturday. At least 38 of those on board have been confirmed dead.

As of early Sunday morning local time, search and rescue efforts remained underway for those who are still missing, according to state media outlet Vietnamnet.

The vessel was carrying 53 people – 48 tourists and five crew members – according to local paper VN Express.

In an interview with Vietnamnet, a 64-year-old diver at the scene said much of the ship’s passenger area had been searched. The cockpit and engine room, however, are stuck in mud, making them harder to reach.

“As of now, I am certain there are no more bodies in the passenger cabin,” said diver Đinh Khắc Giông. “I only worry that some bodies may have drifted outside.”