Los Angeles: Singer-actress Hilary Duff has been warned by police that an obsessed fan is trying to propose to her after he hired a limousine driver to try and find her house. The 28-year-old star was contacted by officers in Beverley Hills after they became concerned about the unnamed man's odd behaviour. According to tmz.com, the ordeal started earlier this month when he hired a limousine driver and had a photograph of Duff's house but didn't know the full address. So he got the driver to search for the property for two hours, during which he spoke endlessly about his intent to marry Hilary. When the car journey was over, the driver was so worried that he called the police, who then contacted Duff's team. Insiders claims the former "Lizzie McGuire" star's security team know who the man is and what he looks like as they've had issues with him in the past. However, Duff -- who has a four-year-old son, Luca -- is yet to file a police report or seek a restraining order and, instead, has just upped her security.