Like a select few Congressmen, Britney Spears has been on the receiving end of suspicious packages of late. It started with a few letters, sent once a week. And then the boxes started coming. They're all being sent to the same Los Angeles address, but it's not Britney's. And thank goodness, writes OK!, because what's inside could be bad for her mental stability! EEKers!

"The first thing you see when you open the box is a huge, lavender-colored, battery-operated sex toy," the source tells OK!. "Still with the price tag on it." And alongside the mechanical apparatus are two letters — one handwritten and one written on a computer — both threatening and pornographic in nature.

"The handwritten one is on note paper and it's written in a crazy, all-caps chicken scratch," says the source, who adds that the five-page typed letter contains vivid, pornographic details of the writer's fantasy exploits with Britney, none of which can be printed here.

Perhaps the scariest item inside the package is what some believe to be a picture of the sender — a middle-aged Caucasian male with stringy, greasy hair — with the eyes cut out of the photo, in which he appears to be squirting some sort of yellowish liquid into his open mouth.

"It's like something from a bad movie," says the source. "If I hadn't seen it myself, I wouldn't believe it."

Insiders tell OK! that the packages, which come with a return address in the Minneapolis, Minn., area, are immediately handed over to Britney's security team, who in turn hand them over to the FBI for further review.

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