KAKE-TV reports the accident happened early Wednesday on the Kansas Turnpike.
The Highway Patrol says one school bus was towing another southbound when the towed bus broke loose. Troopers say the driver of the first bus turned around in the southbound lanes and drove back to the other one.
Other motorists tried to avoid the buses, setting off a chain-reaction crash that killed a driver identified as 60-year-old Donald Putman, of Wichita.
Investigators believe the drivers of the two buses recently bought them at auction and were taking them to Mexico. One of the men is from Mexico and the other from Texas. Both are in custody.