Texas Department of Public Safety / AP

A pickup truck crashed into trees in Goliad County, Texas, on Sunday, killing at least 13 people and injuring 10 others, authorities said.

Updated at 5:31 p.m. ET: Fourteen people died after a pickup truck loaded with suspected illegal immigrants veered off the highway and crashed into trees in rural South Texas, authorities said.

State troopers and Goliad County sheriff's investigators were investigating Sunday's crash. A trooper told KRIS-TV, the NBC affiliate in Corpus Christi, Tex., that it appeared a tire on the truck blew out before the vehicle went off the road and struck two trees.

Authorities said they did not immediately know the names and ages of the victims.

Federal officials believe the 23 people riding in the Ford pickup truck were from Mexico, Guatemala and Honduras.

"We suspect at this time it is going to be illegal immigrants that were in the vehicle, based on the way they were traveling,'' said Lt. Glen Garrett of the Texas Department of Public Safety, Reuters reported.

Vehicle laden with passengers
Gerald Bryant, also of  the Texas Department of Public Safety, told The Associated Press the dead and wounded were various ages and included at least two young children.

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

The pickup was heading north on U.S. 59 around 7 p.m. (9 p.m. ET) Sunday when it traveled off the right side of the highway near the community of Berclair in Goliad County, Bryant said.

The 23 people were loaded inside both the truck's cab and bed.

Six of those who died were still inside the truck when emergency crews arrived to find the mangled vehicle, Bryant said. A man who claimed to have been the driver of the vehicle was ejected but survived, Bryant told the San Antonio Express-News.

He said several of the surviving victims had life-threatening injuries. He 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.

'Very traumatic'
Border Patrol will assist with the investigation, authorities said.

Read more from NBC News station KRIS-TV in Corpus Christi

Crash investigators stayed at the scene into the late hours Sunday to assess the crash, which halted traffic on U.S. 59. "It's been very chaotic here, and it's very traumatic," Bryant told the Express-News earlier from the scene. "It's only first responders out here, and it's very solemn."

The Associated Press contributed to this report.

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A pickup truck crashed into a van carrying high school basketball players on Friday, killing two of their coaches and another man, Nebraska authorities said.

The accident happened along Highway 2 in rural central Nebraska just west of Ansley, a small town about 160 miles west of Lincoln. 

The State Patrol said the van's driver, 38-year-old Zane Harvey, and his front-seat passenger, 24-year-old Anthony Blum, were killed. The truck's driver, 70-year-old Albert Sherbeck, also died. 

The patrol said Harvey and Blum, both coaches at Broken Bow High School, were driving students home from a basketball clinic in Kearney when an eastbound truck crossed the centerline and hit their westbound van head-on. 

Eight boys were taken to hospitals, including two who were treated and released, according to the patrol. 

The conditions of the other six boys haven't been released, though a message on the school's website said they were seriously injured. A ninth student who was originally believed to be in the van had ridden home with a relative. 

A vigil was scheduled Saturday morning at the school.

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