The bodies of a man and a woman were found in a swimming pool at a British hotel, where a murder mystery party was planned.

Medical examiners are performing autopsies on the bodies of the woman, in her early 20s, and the man, in his early 30s, who were both from London, according to a Sky News report.

Staff members at the Down Hall Country House Hotel in Essex, England, discovered the bodies in the water Saturday night and dived in to try to save the victims. Despite the best efforts of staff members and emergency responders, they could not revive the victims, who were pronounced dead at the scene.

A murder mystery game was scheduled to start at the hotel Sunday, but it was canceled after the bodies were found.

Essex Police investigating the deaths have not determined a cause, and are focusing on the relationship between the victims. Chief Inspector Nick Lee told Sky the police are not looking for any suspects in connection with the deaths.

Guests who showed up at the hotel to attend the murder mystery party thought the cancellation and police presence at the hotel was part of the game.

"So we drove down here and saw all the police here and even then I thought it was just a hoax," guest Frankie Heritage said. "Then I walked in and asked a member of staff about it and they were sort of sworn to secrecy. They said they didn't know anything. But I still thought it was part of the murder mystery weekend."

The luxury hotel — located in the countryside 45 minutes outside London — is an old Italian mansion that dates back to 1322.

Hotel manager Chris Falcus said Down Hall employees are cooperating with police and are "devastated" by the incident, adding, "Our thoughts are with the families and friends of those concerned.”

Click for more from Sky News.