cowellmezhgan051311_02_X17.JPGSimon Cowell had a scary run-in with an intruder at his London home on Saturday, but thankfully the X Factor judge is alright after the incident, which is now being handled by the police.

Cowell found 29-year-old Leanne Zaloumis armed with a brick, and she had been wandering around his house after breaking and entering -- literally! -- by smashing in a window. "The woman who was in his house clearly has some sort of mental problems," a source tells Us Weekly of Cowell's intruder. "She roamed around the house, lied in his bed, [and went] through his bathroom." Hmm, sounds kinda like that kooky Alanis Morissette song...

Cowell's rep Max Clifford told The Sun that his client heard a loud noise and rushed upstairs to check it out. "It came from the bathroom, so he went in – and there was a woman standing there holding a brick," Clifford said. "She had smashed her way in through the window, and it was unclear how long she had been there or what she was doing. It was a very frightening experience for Simon, who told me it was like something from a horror movie."

Zaloumis was later charged with trespassing on the property and intending to "inflict grievous bodily harm upon a person therein," according to Reuters.