A book bag apparently prevented a 12-year-old Massachusetts boy from being crushed by a school bus on Friday, March 10. The Associated Press reports that the boy was dragged 20 to 30 feet by the bus after he was struck while crossing a school driveway in Holbrook, Mass. A fire official said the heavy book bag jammed under a tire, preventing the bus from rolling over the boy. A witness chased the bus and told the driver to stop. Emergency workers freed the boy by cutting the straps of his book bag. He was taken to a hospital and released in less than an hour. Police said the bus driver didn’t see the boy. An investigation is underway.