VAN HORN, Texas (AP) — A Texas sheriff who was among the first people to reach two U.S. Border Patrol agents who were badly injured says he thinks they were hurt in an accident, not an attack.

Culberson County Sheriff Oscar Carrillo told The Dallas Morning News that the agents, who were found along a culvert next to Interstate 10, may have been sideswiped by a passing tractor-trailer.

Agent Rogelio Martinez died of his injuries and his partner was hospitalized after they were found Nov. 18 near Van Horn, about 110 miles (175 kilometers) southeast of El Paso.

President Donald Trump, Sen. Ted Cruz and Texas Gov. Greg Abbott have said the two were attacked.

Federal officials have released few details about the circumstances leading to their injuries.