UNIVERSITY OF ILLINOIS - Someone breaks into a U-S Post Office on campus, but they didn't take anything. Investigators say it's an unusual case. Tony Ortiz from the University of Illinois Police says, "Since I've been here almost twenty years, it's the first one I've heard of." In Crime Watch tonight, police say the culprits may have been looking for money, stamps or credit card information. But even though they found nothing, police still want to find them. It happened around four in the morning on May 31st at the post office in Altgeld Hall at 1409 West Green Street in Urbana. They pried open one of the service counter windows, setting off a silent alarm. But when officers arrived, they were already gone. Ortiz says it's possible they were scared off by someone else. Ortiz says, "Graduate students work different hours in that building, late at night and early in the morning, so maybe somebody came by and alarmed them and they went away." There have been other break-ins at campus buildings in the last several months, but in those cases money was taken. No word on whether this case is related. By the way, breaking into a post office is a federal offense. If you have any information about this case, call Champaign County Crimestoppers at 373-TIPS. You don't have to give your name or testify in court and a reward is offered.