Authorities are investigating a crash involving a UAB employees on a bus in Winston County. State troopers say eleven people were injured, two seriously, after the bus rolled down a hill and struck a large rock, then a tree. A spokesperson for UAB says the employees involved were all pediatric residents who were returning from a retreat at Camp McDowell. The university says it is working to contact families. UAB says 26 of its employees were involved in the crash. State troopers say of the eleven injured, seven were taken to UAB Hospital for treatment. Two have serious injuries, and four were taken to Cullman Regional Medical Center in Cullman for treatment.