Ozzy and Sharon contact police over party 'thief'

Ozzy and Sharon Osbourne claim an uninvited guest illegally took a diamond necklace from their New Year's Eve party.

They say the woman gatecrashed the casino-themed event at the Beverly Hills Hotel, where she won the necklace in a raffle.

The couple have contacted police in Los Angeles over the incident, which they say has "left a very bad taste in their mouths."

According to MTV.com, the ICM talent agency employee is alleged to have won a raffle that she should not have been eligible to enter.

The Osbournes say they asked her to return the Asprey-designed diamond necklace, which is valued at $42,000 in the police report, the following day but she refused.

A statement by ICM says it "categorically denies the false and reckless charges made by Sharon Osbourne", adding the agent in question was "a close friend" of the family.

ICM claims she won the raffle for the necklace in a fair manner, "without any inappropriate conduct".