About 60 Ackerman High School seniors had been visiting the campus of the University of Mississippi at Oxford and were returning home aboard the buses on Mississippi highway 8, about 40 miles south of the college.
Students were taken to area hospitals, none with life-threatening injuries, troopers said in a news release. One student was taken by helicopter to North Mississippi Medical Center in Tupelo.
Mike Dunagin, fire chief of Calhoun City near the scene, told The Associated Press that one of the buses smashed up against the guard rail of a highway overpass bridge. Photos showed one bus with its rear half dangling over the guard rail, its hood crumpled and sheered away on the driver's side.
"We're very fortunate the bus didn't go off the bridge," Dunagin said.
The 18-wheeler swerved into the wrong lane and hit the buses, said Mississippi Department of Public Safety spokesman Jon Kalahar.
Killed were trucker Gary T. Bailey, 54, of Mantachie; the driver of the second bus, Steven B. Moss, 37; and Ackerman high teacher Phyllis Graham, 53, of Eupora, highway patrol troopers said. Graham was a passenger on the bus, and Moss also taught and coached at the high school in Choctaw County. The driver of the first bus hit, Shane Burton, 40, of Ackerman, had minor injuries, police said.
Several emergency crews and some pastors to help with counseling were at the scene to assist the shaken students who were some 40 miles from home, said Charlie Brown, a spokesman for the Calhoun City Fire Department.
"Most of them were in total shock," he said of the students.
Associated Press Writers David Brandt and Shelia Byrd in Jackson and Chevel Johnson in New Orleans contributed to this report.