The two vehicles were left mangled and charred after the crash ignited an oil-fed fire.
Police said two people were killed in the crash and Saturday night, the Posen Fire Department confirmed one of them was one of their own, 25-yaer-old Zack Orel, a firefighter-paramedic who joined the department last summer.
The Will County Sheriff's Department said a Chevy Trailblazer and a Ford Mustang were moving at a high rate of speed as they drove beyond a dead end through a fence and into an oil pipeline owned by the energy company Enbridge.
Firefighters rushed three men to Silver Cross Hospital in Joliet for treatment, said New Lenox Fire Protection District Chief Jon Mead said.
Two men were soon transferred to the burn unit at Loyola University Medical Center in Maywood, New Lenox police Chief Bob Sterba said. One man was so badly injured, he was airlifted via helicopter, he said.
The five men are all in their 20s and reside in New Lenox, Sterba said.
New Lenox Mayor Tim Balderman said he knew "a couple of the kids" involved in the accident.
"They were just regular kids from the neighborhood, good kids, good families," Balderman said.
In a written statement Posen fire Chief Keven Szewczky said Orel "was very well liked and a friend of all. He came in to every shift with a smile on his face. He will be missed by all and his death will be a tremendous loss to the Posen Fire Department."
The crash caused a leak of an undetermined amount of oil and hazmat teams spent all day cleaning up the mess.
"They were able to seal it fairly quickly," Balderman said. "There was a great deal of oil, though, that did spill out and that's why the flames were so terrible, so big. My understanding, though, in talking with Enbridge, is there is no impact, there's no environmental issues, nothing that we need to be concerned about."
(The Sun-Times Media Wire contributed to this report)