Authorities are investigating after a 5-year old boy was run over by a garbage truck in southwestern Illinois.  Police say the boy was hit by an Aspen Waste Systems Incorporated garbage truck shortly before 4 PM, Wednesday in Fairview Heights while he was riding a bicycle in the street.  The boy suffered extensive injuries to his lower body, but was conscious and talking when officers arrived.  He was airlifted to a hospital in Saint Louis, where he was listed in critical but stable condition.  No charges have been filed against the garbage truck driver.