A source close to Lohan says her security guards are looking into the matter and trying to contact the man.

Lohan made reference to an unwanted admirer in the July issue of British GQ, though it was unclear whether it was the same individual who's been sending her letters of late writes Eonline.

"I have one really bad stalker," the actress said. "He says he's going to be at the Chateau Marmont before my birthday and prove to me that we're meant to be together, even if he has to take me away and teach me. They have a picture of him there. It's scary."