Update: Playboy Model Threatens to Sue Spencer Pratt Over Sex Tape

Another day, another Speidi sex tape scandal.

Playboy model Karissa Shannon is threatening to sue Spencer Pratt, who is allegedly in possession of a sex tape featuring Shannon and her boyfriend, Sam Jones.

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Shannon's laywer Hayes F. Michel fired off a letter to the Hills villain Thursday, requesting that he return the footage that "was taken from her possession" and "contains private materials," TMZ reports.

"It had been reported in the press that you were attempting to publish, distribute, sell, license or otherwise exploit filmed footage of Ms. Shannon. According to press reports, you are no longer threatening to do that. This decision is wise," Michel wrote. "Were you to follow through with your initial threat, Ms. Shannon would file a lawsuit to enjoin the sale and/or distribution and seek monetary damages from you."

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Michel requests that Pratt, 26, contact him immediately to make arrangements to return all copies of the tapes. Additionally, Pratt is being asked to provide written acknowledgment that he will no longer attempt to "publish, distribute, sell, license or otherwise exploit the footage." Finally, Michel is asking for a list of people and/or companies who have seen or received the tapes.

Pratt addressed the letter on his Twitter account Monday. "Maybe if I threaten to release a solo sex tape, humanity will pay me $5 million not to," he tweeted. "Would love to give Karissa Shannon her sex tape back, but it's currently serving as the keystone of my awesome sex tape fort."

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Last week, a source confirmed to UsMagazine.com that sex tapes starring Shannon and Pratt's ex Heidi Montag do exist, though they may be kept under wraps -- for now.

"There's more than one. But that doesn't mean they'll ever see the light of day, despite Pratt's threats," a source told Us. "This is all a PR stunt, They will never really sell unless they get desperate."