At least nine alleged undocumented immigrants were killed, and six others wounded, when the cramped van they were travelling in crashed at a Border Patrol traffic stop in southern Texas. 

Most of those involved in the crash in Palmview around 10:30 p.m. Tuesday were Mexican citizens, according to Enrique Mendiola, acting assistant chief for the Border Patrol's Rio Grande Valley sector.

The van was demolished, but four men managed to flee the wreck, said police Cmdr. Lenny Sánchez. Two were caught and two remained at large early Wednesday, Sánchez said.

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The van, designed to carry a driver and up to seven passengers, had been gutted to squeeze in 19 people who authorities believe entered the country illegally, he said.

Mendiola said the accident occurred on U.S. 83 after Border Patrol agents stopped the van and another vehicle. Some of the passengers fled the van and agents pursued them on foot, catching one, Mendiola said. Then the van took off.

He said the agents returned to their vehicle and came across the wreck three or four blocks away. The scene was strewn with backpacks and water bottles, and nine covered bodies lay scattered within 30 yards of the van, Mendiola said.

The other vehicle was not identified.

A 23-year-old woman who lives nearby told the McAllen Monitor that she didn't see the accident happen but that crash victims seemed to be alive in the immediate aftermath.

"The bodies were still moving. The bodies were everywhere," Diana Castillo said.

Mendiola said authorities were working with the Mexican consulate to identify the dead.

"It's really sad because they came over here to live a better life and then they lost their lives," Castillo said.

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Three women have been treated at a hospital and released to immigration authorities, Sánchez said. Three men remain hospitalized Wednesday. Sánchez has no details on their conditions. The nine people who died were men.

Weather was not believed to be a factor, Sánchez said. Conditions were clear and dry at the time of the accident, according to the National Weather Service.

Palmview is 10 miles west of McAllen.

Based on reporting by The Associated Press. 

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