Fort Collins detectives say there's been a rash of home invasions in which armed robbers force their way into homes looking for marijuana. In at least two cases, the bandits thought their victims were legal medicinal marijuana users, according to 7News , and police worry that eventually a victim will be harmed. It's so bad that one officer warns, "If you're not expecting someone, don't answer the door, and call police if you're suspicious of the person there." The home invasions began on November 16, according to theÂ Fort Collins Coloradoan , when several men unsuccessfully tried to force their way into the home of medical marijuana providers. Of course, the thieves are open to stealing other drugs or cash, too.