Credit: Chris Jackson/Getty Images; Christopher Furlong/Getty Images

Sad news in the royal world.

British police are treating the discovery of a woman's body on Queen Elizabeth's Sandringham estate as murder, the Associated Press Reports. (Human remains were found on the land in Norfolk on Monday.)

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Prince William and Duchess Kate spent their first married Christmas at the Queen's Sandringham estate, before heading to Bucklebury to spend time with the Middleton family.

According to the Associated Press, Sandringham has served as a private residence for British monarchs since 1862.