Russian-born New York socialite and real-estate mogul Janna Bullock has hired uber-publicist Max Clifford to battle a malicious Facebook campaign that falsely claims she's massacring mustangs by organizing safaris in which wealthy hunters shoot the wild horses with poison.

Clifford is a famed British-based publicist whose clients have included David Copperfield, Simon Cowell, Harrods owner Mohamed Al Fayed and Rebecca Loos, who claimed an affair with David Beckham.

The Facebook page, titled "Stop the killing of mustangs! Stop Janna Bullock," reads, "For over two years the Russian mafia lady is illegally killing the best American racers in order to sell pictures made on their hides." It also claims Bullock, a trustee for the Guggenheim Museum, charges $100,000 for safaris at private reserves out west.

They travel in cars and shoot at them. But they did not shoot bullets," the page claims, alleging that the hunters use ampuls of poison. It goes on: "This is not to damage the skin . . . from which they make paintings. The poison acts very slowly until the animal dies, the Russian offer to drink vodka over a dying animal, to celebrate the victory."

Clifford blasted the campaign as "nothing but a malicious lie designed to discredit Janna Bullock's name."

Her New York lawyer, Robert Wolf, told us in a letter: "[She] has been the subject of a malicious, defamatory campaign amounting to criminal harassment by anonymous, if not fictitious individuals who have exploited the Facebook Web site."

Wolf has asked Facebook to take down the page, which appears to be administered by a fictitious "Suzy Armstrong."

It's believed the campaign, which has fired off Facebook messages to prominent New Yorkers, can be traced to Moscow, where Bullock's politician husband, Alexey Kuznetsov, is being probed for a $1 billion fraud.

"This is indicative of some of the smear campaigns coming out of Russia designed to attack her and her husband," Clifford said.