National Sea Rescue Institute

A popular tourist excursion near Cape Town, South Africa, turned into a horrifying experience for dozens of people when their boat capsized in chilly, shark-infested water. Three of the tourists trapped beneath the boat for hours this weekend survived by finding air pockets. Two men died.

The charted catamaran Miroshga was near Hout Bay on the way to Duiker Island where the 34 tourists, including four children, and four crew members were headed to see a famous seal colony. The area is also known for its population of great white sharks. The boat capsized shortly after 2 p.m. Saturday, according to the South African National Sea Rescue Institute.

"Upon arrival, we found many of the passengers had been pulled onto fishing boats and chartered tourist boats that were nearby or were clinging to the side of the upturned boat," the institute's Craig Lambinon said.

One of the passengers, Peter Hyett, 64, of the United Kingdom, was unconscious and could not be revived. Rescuers immediately started search operations for the four passengers who were still missing.

"Rescuers moved onto the hull of the boat and used tools to bang on the upturned top of the boat to see if they got a response, and they did get tapping back so they knew there were people trapped beneath the boat," Lambinon said.

Anna-Marie Weaver of South Africa told the Cape Times she was one of those trapped passengers.

"It was dark in there," Weaver told the Times from her hospital bed Sunday. "The boat was moving and the water rushing backwards and forwards, very strongly. I don't know how long we were in there when we heard someone shouting from outside, knocking on the hull. When I heard that voice, it was like a sound out of heaven."

Rescue divers then began searching for the trapped passengers. About two hours after the boat capsized, they found one woman surviving in an air pocket in the hull. They continued looking for another two hours before they found more trapped passengers.

"They had searched most of the boat and found nothing. Then in a section of the boat that was almost barely accessible, they found another two women surviving in an air pocket in a cupboard," Lambinon of the Sea Rescue Institute said.

Lambinon said it took about 30 minutes for rescuers to encourage the frightened women to give up their life jackets so they could swim out of the boat. The body of the fourth missing passenger, South African tour guide John Roberts, 37, was found the next day on the bottom of the ocean near where the boat capsized.

The survivors were treated for hypothermia and minor injuries. Weaver is the only passenger still in the hospital and is expected to make a full recovery.

The catamaran has been recovered from the water, and the cause of the accident is now under investigation.