Troy Police Department Sgt. David Lowry said the military Humvee drifted off Interstate 65 on Wednesday before striking and vaulting over a concrete barrier, crashing into an oncoming Toyota Corolla, the Waco (Texas) Tribune-Herald reported Thursday.
The driver of the Corolla, 41-year-old Douglas Ashcroft, was killed in the collision.
The Humvee then struck a tractor-trailer, killing 44-year-old Donald Johnson, and landed upside-down on the interstate's northbound lanes. The Humvee's driver, 21-year-old Altha Gibson, also died in the crash.
Lowry said the collision made the tractor-trailer jackknife and strike a pickup that was towing a sport utility vehicle, before a trash compactor truck collided with the semi.
The compactor truck driver was not hurt in the crash and the pick-up truck was not occupied at the time of the collision.
Lowry told the Tribune-Herald it remains unclear what caused Gibson to initially drift off the interstate.