Canadian authorities have called off their search for six people who were reported missing after their charter boat sank near Vancouver on Sunday.
The emergency call of people in the water without life jackets about 10 miles (16km) off the coast came in at 11:45 PT (17:45 GMT), according to officials.
Three survivors were rescued by a couple on a sailboat in the area, and a fourth person was rescued by search crews.
On Monday evening, authorities said that the four men and two women who remain unaccounted for are presumed drowned.
“We covered the area extensively,” the officer in charge of the rescue mission told CBC News earlier on Monday, adding that they are confident they have “exhausted all possibilities of finding anyone on the surface alive”.
The charter boat began to take on water near the area of Roberts Bank, after departing from Steveston, a historical fishing community in Richmond, British Columbia.
The search involved passenger ferries in the area, as well as Coast Guard and Royal Canadian Mounted Police (RCMP) boats, helicopters and airplanes.
Major Gregory Clarke, the officer-in-charge of the Joint Rescue Coordination Centre in the nearby city of Victoria, told CBC, external that it is not yet known what caused the ship to sink.
“We have no idea at this time,” he said.
The identities of those who remain missing were not yet shared.
Clarke told the Vancouver Sun newspaper that there was initially a language barrier with the survivors, which was compounded by hypothermia, but they were able to tell rescuers there were 10 people on board when the vessel sank.
A couple on a sailboat are being credited with saving lives by alerting authorities to the emergency.
Brian Angus and Dorothy Stauffer, who rescued three people from the water, told CBC they saw no wreckage or debris at the scene, and that none of the people in the water were wearing life jackets.
Asked how they were feeling more than 24 hours after the rescue, Stauffer told CBC: “I didn’t sleep a lot, and I thought a lot about it throughout the night – replayed it in my mind quite often.”
She said her training as a flight attendant helped her during the rescue, adding that she was grateful they found the people in the water when they did.
“I am so happy that we were there at the right time,” Angus said.
Still, the couple said they were devastated that they couldn’t rescue more people.
Officials have not yet identified the name of the boat that sank, but have described it as “a commercial charter vessel”.
In the update on Monday, the RCMP said that an underwater recovery team “will attend the area in the coming days to locate the capsized vessel using sonar”.
The team will then decide whether it is possible to dive to the sunken ship, or whether a drone will be used to access it.
“The vessel is believed to have sunk in very deep waters,” the RCMP statement said.
Of the survivors, a 26-year-old man and a 33-year old woman have been discharged from hospital.
Two others – a 33-year-old man and a 28-year-old woman – remain in hospital in a critical condition.
