A pickup truck crammed with at least 23 people, many of them undocumented, crashed into a tree and killed at least 14 people.

The dead include 11 men and three women who had immigrated from Mexico, Honduras and Guatemala, said a spokesman for the U.S. Immigration and Customs Enforcement. At least nine people remain hospitalized, said ICE spokesman Greg Palmore.

The 2000 Ford F-250, which was jam-packed with people in its cab and bed, was heading north on U.S. 59 about 90 miles southeast of San Antonio when it suddenly veered off the highway onto two trees, said Gerald Bryant, a spokesman for the Texas Department of Public Safety. Among the dead were two children, Bryant said. No other vehicles were involved.

This is the most people I've seen in any passenger vehicle, and I've been an officer for 38 years."

- Gerald Bryant, a spokesman for the Texas Department of Public Safety

"This is the most people I've seen in any passenger vehicle, and I've been an officer for 38 years," Bryant said, referring to the chaotic scene.

Authorities say they do not know why the vehicle lost control. The names and ages of the victims has not been released.

Six of those who died were still inside the truck when emergency crews arrived to find the mangled vehicle, Bryant said.

Several of the surviving victims had life-threatening injuries. Bryan did not have their official conditions but described them as "very serious." The injured were taken to various hospitals in San Antonio, Victoria and Corpus Christi. Berclair is about 100 miles southeast of San Antonio.

Border Patrol will assist with the investigation.

Crash investigators stayed at the scene into the late hours Sunday to assess the crash, which halted traffic on U.S. 59.

Based on reporting by The Associated Press.

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