Engine 751 and Ambulance 751 were alerted along with Montgomery County Rescue Squad 741 for the traffic collision at the intersection of Old Georgetown Road and Center Drive.  Crews arrived to find 7 vehicles involved, including a passenger bus, with several patients laying in the grass.  In all, 4 patients were transported.  Responding Crews were: Engine 751- OIC- MFF Weaver, Dr- Tech. Rule, RB- Tech. M. Gilroy.  A751- OIC- MFF Piles, Dr.- Tech. Byard