Police are investigating a burglary at a school in Rockville Centre.Officials say someone broke into an office Tuesday night at South Side High School. According to police, cash was taken during the incident. It was initially reported that a BlackBerry cell phone was taken, but that device has been located.The school's assistant principal says she was shocked to hear about the incident. Noreen Leahy says this is the first time an office at the school has been broken into in the seven years she has worked at the high school.Police say they are still trying to determine who may have wanted to break into the office. The school does have a video surveillance system, and school officials say tapes will be reviewed in an attempt to get more information on the burglar.