An investigator for the National Transportation Safety Board says a collision in northeast Arkansas involved a train with two locomotives and 86 cars and another with two locomotives and 92 cars.
Investigator Michael Hiller says the first train was northbound on a single main track early Sunday when a southbound train collided with it. He says they were on the same track.
State police have said two Union Pacific train crew members were killed and two others were injured.
Hiller said the cause of the accident has not been determined and he expects investigators to be on the scene about a week.
The collision happened about 3 a.m. in Hoxie, about 90 miles northwest of Memphis, Tennessee. Union Pacific says a resulting fire took about seven hours to extinguish.