CEDARHURST - A school bus collided with a commuter bus in Cedarhurst this morning, leaving 30 people injured.The accident happened at around 9 a.m. at the intersection of Central Avenue and McGlyyn Place. Fire officials say all 15 preschool students from the Lawrence School District who were aboard the bus sustained injuries, but are expected to recover. Deputy Chief Anthony Rivelli, of the Lawrence Cedarhurst Fire Department, says the kids were transported to Nassau County Medical Center as a precaution. Rivelli says the most serious injury on the MTA bus was a possible fractured leg. Some of the other passengers suffered head, neck and back injuries. Police say the cause of the collision is being investigated. However, Chris Lewis, who was on the MTA bus, claims the driver ran through a stop sign and broadsided the school bus.