VAN HORN, Texas (AP) — Authorities were scouring West Texas on Monday for those behind an apparent attack that killed one U.S. border agent and injured another. U.S. Customs and Border Protection issued a statement Sunday that was thin on details about what happened, saying the two agents "were responding to activity" while on patrol near Interstate 10 in the area of Van Horn, which is about 30 miles (48 kilometers) from the border with Mexico and about 110 miles (175 kilometers) southeast of El Paso. CBP spokesman Douglas Mosier said 36-year-old agent Rogelio Martinez and his partner were transported to a hospital, where Martinez died.