Did someone finally move into the empty house down the street that’s been for sale forever? They might just be pretending to own it. According to MSN Money, more and more people are becoming “luxury squatters,” and moving into vacant, bank-owned houses and mansions – mostly in the middle of the night - changing the locks, and living the high life. You may have heard about the bank executive who was fired last year after she moved into a beach-front mansion in Malibu that her bank had foreclosed on, and threw several fancy parties.

A lot of the squatters defend their actions by citing “adverse possession” – a law that dates back to 16th century England. It lets squatters eventually take ownership of abandoned land – provided they pay the taxes, occupy the land, and maintain and improve it for several years. The law was designed to make sure local governments continued to get taxes on all the property in their jurisdiction.

Today, scammers are using it to justify grabbing bank-foreclosed properties to live in, or rent to unsuspecting tenants for big bucks. One woman in the article took over 11 bank-owned houses in the Seattle area, including a $3-million mansion with a wine cellar, home theater, six bedrooms and nine baths. She’s been repeatedly arrested for trespassing. Another squatter near Tampa, Florida “acquired” 72 homes, found tenants and collected tens of thousands of dollars in rent. The tenants were forced to find other places to live after he was arrested. His lawyer insists he’s just helping maintain neighborhood property values, and keeping empty houses from being stripped and burglarized. In some cities, activists are even helping homeless people move into foreclosed properties, providing them with furniture, cleaning supplies, and gardening equipment to use until they eventually get evicted.

So, how can you protect your neighborhood from squatters? It’s simple. If you think a squatter might be living in an abandoned home, call the police.