ST. AUGUSTINE, Fla. -- Two Flagler College students were killed and three others injured Thursday night after they were rear-ended on Interstate 95 by a tractor-trailer that investigators said failed to stop for slow traffic.

According to the Florida Highway Patrol, Lindsay Chain, 20, of Bay Minette, Ala., and Jessica Kaufman, 18, of Plantation, Fla., died at the scene.

Stephanie Estes, 19, of Jacksonville, and William Anderson, 19, of Key West, Fla., were flown by air ambulance to Halifax Hospital in Daytona Beach, where they are in serious but stable condition.

Troopers said a third student, Kaitlyn Meirs, 18, from Spotswood, N.J., was also injured and treated at Flagler Hospital in St. Augustine.

College officials said some of the students were headed to Orlando to attend a concert when their car broke down. They called a tow truck to get the car and another student to pick them up.

According to the FHP report, the crash occurred about 11 p.m. just before the Old Kings Road overpass as the tow truck and Estes' 2003 Volkswagen were traveling back toward St. Augustine in traffic slowed by road construction. Both vehicles were struck by a tractor-trailer that troopers said failed to slow.

The big rig first rear-ended and rolled over the VW, then struck the tow truck.

The driver of the semi, Miguel Leon, 55, of Ponte Vedra, and the driver of the tow truck, Terry Monroe, 64, of Ovedo, were not injured.

FHP traffic homicide investigators said charges are pending

"All of a sudden, we're faced with a reality: The student that sat next to you all semester is no longer there," Flagler College President William Abare Jr. said. "Those things are very difficult to deal with."

Word spread quickly around the campus of 2,100 students.

"Being at a school like this that's so small, we're a close-knit community," Flagler student Devin Jeffreys said. "It's kind of like a solemn day for all of us."

A counseling center has been established in the Lion's Lair on the Flagler campus, and counselors can be also be reached by telephone at (904) 819-6305.

School officials said that a memorial service will be held on campus early next week, but plans have not been finalized.