A murder mystery with elements of an Agatha Christie whodunit is unfolding at the vast country estate where Queen Elizabeth II and her family gathered in rural splendor to celebrate Christmas and New Year's.
British police said that a young woman's body was found in the forest at Sandringham and that they are treating it as a murder case.
An autopsy was conducted Tuesday, but the precise cause of death was not disclosed, and investigators have yet to establish the woman's identity.
The royal family is not implicated in the crime in any way.
The body was discovered by a dog walker on New Year's Day three miles (5 kilometers) from the queen's elegant country home. Norfolk police said tests showed the body had been there one to four months.
Police said a forensic pathologist found that it was highly unlikely the death was of natural causes and that there was no evidence of accidental injury. Investigators hoped to use DNA to identify the woman.
The queen and her husband, Prince Philip, celebrated the holidays at Sandringham with their children and grandchildren. The royal couple were still at Sandringham on Tuesday, along with their youngest son, Prince Edward, and his wife, Sophie.
Part of the nearly 31-square-mile (8,000-hectare) estate is open to the public, and the body was found at Anmer, a hamlet of several dozen people. Situated 115 miles (185 kilometers) northeast of London, Sandringham has two stud farms and a fruit farm and employs more than 100 people full time.
Forensics investigators in white gear were seen walking through the woods Tuesday in an area cordoned off by police.
"We are at the very early stages of the investigation and it could be a complex inquiry," Detective Chief Inspector Jes Fry said Tuesday. "The body had been there for some time."
Fry said authorities were examining missing-person reports and unsolved cases around the country to see if there were any possible links.
The royal family owns vast tracts of land throughout Britain, and it is not unprecedented for serious crimes to be committed on property under their control.
In 2010, the body of a 46-year-old woman was found on the crown estate near Windsor Castle. She had apparently been killed by hammer blows to her head. Her estranged husband was convicted of manslaughter and sentenced to 26 years in prison.
Last March, the body of an American with a royal obsession was found on an island in the park opposite Buckingham Palace. Authorities said Robert James Moore, who had sent rambling letters and strange packages to the queen, may have been dead for as much as three years. The cause of death was not determined.
Now Sandringham, which has served as a private residence for British monarchs since 1862, has been touched as well.
Sandringham has long been one of the queen's favorite residences, especially during the holidays. The queen has a long-established routine that calls for presents to be exchanged on Christmas Eve, followed by a church service in the morning and a gala lunch. There are usually long walks through the countryside as well.
The royal family also typically enjoys horseback riding and shooting parties at Sandringham in the brisk winter weather.
The New Year's highlight this year was the reappearance in public of Philip, who had to be airlifted from the estate two days before Christmas for emergency treatment after complaining of chest pains. The 90-year-old prince was found to have heart disease and had a stent inserted to keep his arteries open.
Buckingham Palace officials are staying mum about the murder case. Police are keeping many details confidential as they try to develop leads.
"I cannot confirm whether she was clothed because, at the moment, only my staff, the person who found the body and the person or people who put it there know that, and I would like it to stay that way," Fry said.