Three people were killed and a fourth was critically injured early Wednesday morning when a van from an adult rehabilitation center struck a logging truck just outside Folkston, according to the Georgia State Patrol.

Troopers said the van transporting clients of Satilla Community Services rear-ended a tractor-trailer that was stopped at a four-way stop at the intersection of state Road 252 and Indian Trail, which is also known as the U.S. 301 bypass.

Witnesses said the logs slid into the van, killing three people and trapping the fourth.

The van's driver, Coriendiha Moore, and two clients, Elizabeth Jones and Jimmy Harrin, were killed instantly.

John Robinson was flown by air ambulance to Shands-Jacksonville Medical Center.

The driver of the log truck was also hurt and transported to Shands.

Authorities are still investigating why the driver didn't stop for the big rig. Troopers speculated that he either fell asleep or had a heart attack.

The director at Satilla didn't want to give an interview to Channel 4's Jim Piggott, but said the entire staff and clients were in a state of shock.