The families of four missing British yachtsmen are imploring the U.S. Coast Guard to resume the search for the men, whose boat capsized in the mid-Atlantic.

The Cheeki Rafiki was returning from a regatta in Antigua when it ran into trouble about 1,000 kilometers (620 miles) east of Cape Cod, Massachusetts, on Thursday. The 40-foot, high performance Beneteau yacht diverted to the Azores, but contact was lost on Friday.

File photo of the missing yacht Cheeki Rafiki, which has capsized in the mid-Atlantic. Families of four missing British yachtsmen want the U.S. Coast Guard to resume the search for survivors. (AP Photo/Royal Yachting Association/PA)

U.S. and Canadian aircraft, assisted by three merchant vessels, scoured the ocean, but called off the search Sunday amid treacherous weather.

Graham Male, father of 23-year-old crew member James Male, said the men could be adrift in a life raft. He said Monday the families are asking the British government "to put pressure on the U.S. Coast Guard and the Canadian(s) to reinstate the search."

The cargo vessel Maersk Kure Saturday spotted an overturned hull in the search area that matched the description of the missing yacht but saw no signs of survivors or a life raft in the vicinity.

Family members believe the crew may be trapped but alive underneath the overturned hull if there is an air pocket allowing them to breathe.

However, rough seas prevented the Maersk Kure from getting a closer look at the hull, said Doug Innes, director of Stormforce Coaching, the British charter and training firm that had been in regular contact with the crew on its voyage home.

Kay Coombes, the sister of one of the missing crew members, said she is convinced they are still alive.

"They are four strong-minded, physically strong sailors, they knew they were in difficulties and had every opportunity to get into the life raft which would have had provisions for several days," she said. "But if no one is looking for them, they won't be found."

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