Four people remain in the hospital after Friday’s hotel shuttle accident in College Park, police said.

Two passengers are in Grady Memorial Hospital and two more at Atlanta Medical Center. All are in good condition, College Park Police Sgt. Keith Stanley told the Atlanta Journal-Constitution Tuesday morning.

A shuttle bus carrying 15 passengers late Friday morning slammed into the rear of a tractor trailer that was making a U-turn on Loop Road just south of Virginia Avenue.

The truck driver was not injured, but the bus driver and all passengers were taken to area hospitals.

Police, with the help of the Georgia State Patrol’s special collision reconstruction team, continues to investigate the crash.

Stanley said the investigation could take up to two weeks, “before anybody might be charged.”