LAS VEGAS -- State troopers say two people were killed in an early-morning wreck Thursday.

Shortly before 5 a.m., police responded to an "unknown" disturbance on Interstate 15 near Silverado Ranch Blvd. Once at the scene, officers found two people dead on the side of the interstate.

According to witnesses, a man was laying or kneeling in the interstate and a woman was standing beside him. Each was by separate tractor-trailers and several other vehicles afterward, police said.

Officers were able to stop one of the truck drivers they think was involved in the collision. They are questioning him, as well as a second truck driver, in connection with the wreck. They are also seeking a third truck driver who may have witnessed the incident.

I-15 is shut down in the area. Traffic is being diverted onto St. Rose Parkway and re-entering at Silverado Ranch Boulevard.