Hilary Duff has apparently amped up her security this week after being alerted by the Beverly Hills police that she has a stalker, TMZ reports The site claims that the police department personally reached out to the actress' team to warn her about an obsessive man. Apparently, the man rented a limo earlier this month, and had the hired driver navigate the streets for two hours while he looked for Duff. While in the car, he talked about marrying her, and was apparently carrying a picture of a baby crib that he said belonged to the actress.The driver of the limo was so creeped out by the man that he called the police shortly after. TMZ also says they spoke to sources close to Duff who said that the man has been a problem before, and they know what he looks like and who to look out for. As of now, no official police report or restraining order has been filed by Duff.The fact that the star also has a 4-year-old son makes the situation even more terrifying.