Two people died in a fiery car crash in Dallas on August 21, 2012. (credit: KTVT/KTXA)

DALLAS (CBSDFW.COM) – Illegal racing and alcohol are believed to have caused a deadly seven-vehicle pileup in Dallas that cost two people their lives and sent three others to the hospital.

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It happened early Tuesday on southbound Interstate 35E in Oak Cliff.  “They were racing,”  Jay Bivens told CBS 11 News.  He was helping a disabled car when he says he saw a Chevrolet Chevelle and another car begin racing. The Chevelle, he says, looked unstable right away.

“Before he got to the Illinois exit, he almost lost control then,” Bivens said.

Sheriff’s investigators say a red Cadillac, not part of the race, inadvertently tagged a guardrail and bounced into the Chevelle. The Chevelle, in turn, rear-ended a big rig in a fiery crash, nearly splitting it in two, and triggering a chain-reaction wreck consuming seven vehicles.

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Two people in the Cadillac died; three other people were hospitalized.  “They (car victims) didn’t know what happened. It all happened at once. They didn’t know, the 18-wheeler didn’t even know. The car had hit him in the back,” according to Bivens.   “I have seen stuff before but it’s the first time I’ve seen someone—-what’s it look like when a crash dummy hits a car? That’s exactly what happened.”

Investigators say what happened was not an accident, but a crime.  “They were racing,” according to Carmen Castro of the Dallas County Sheriff’s Department.   “We’ve made an arrest for criminally negligent homicide; we still need to confirm the identity of that individual,” she said.

Sheriff’s deputies are not identifying any of the victims, saying so many aspects of the case are still under investigation. They also had their hands full with traffic. “Deputies had to block one of the on-ramps because there were vehicles exiting the wrong way.”

Castro says investigators believe alcohol was a factor and are doing toxicology tests. They are also trying to determine if the other car racing the Chevelle was in the wreck; Bivens believes it got away.  The driver of the Chevelle was one of those hospitalized.

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