PIC: Lindsay Lohan Holds a Gun to Her Mouth

Lindsay's got a gun.

On Wednesday night, Lindsay Lohan, 23, posted an eerie new photo on Twitter -- in which she holds a gun to her mouth.

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Her caption explains that the grainy shot (she appears heavily made up, holding up her long dark hair with her free hand) is a "Polaroid from [a] shoot."

It's not the first time Lohan has brandished dangerous weapons with a come-hither look on her face: in 2007, sultry pics of her and Vanessa Minnillo playing with knives hit the web.

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The new gun snapshot comes at a time when Lohan's father Michael claims that he fears for his daughter's life. Following a failed attempt to stage an intervention, Michael Lohan said via his attorney that he wants to "save and protect his daughter" from what he calls a "serious drug [and] alcohol problem." The estranged dad, his lawyer Lisa Bloom said, wants to "prevent Lindsay from becoming another Marilyn Monroe, Anna Nicole Smith, Michael Jackson, Heath Ledger, or Corey Haim."

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Lohan has denied that she uses drugs; her mother Dina recently told us that the plan to file a restraining order against Michael.