NEW BRAUNFELS, Texas (AP) — Authorities in two Texas counties say they received phone calls about a white pickup truck swerving along the roadway shortly before a head-on collision between a church bus and a pickup killed 13 people.

Uvalde police Lt. Daniel Rodriguez says a man called around noon Wednesday to report the erratic truck heading north on U.S. 83. Deputies were dispatched, but Rodriguez says the same person called back less than 30 minutes later to say the truck crashed.

Real County Constable Nathan Johnson also says a woman called to report a truck matching the description was swerving in the same area shortly before the collision about 75 miles (120 km) west of San Antonio.

One person from the bus and the pickup driver remain hospitalized.

On Thursday, National Transportation Safety Board investigators began looking into the crash.

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