UPDATED 08/07/12 – 4:56 p.m.

CHICAGO (CBS) — An Illinois Department of Transportation minuteman was just trying to help a driver in need, but he is now in a hospital room with critical injuries after a hit-and-run accident on the Dan Ryan Expressway.

As CBS 2’s Susanna Song reports, the minuteman was 42 years old and a U.S. Army veteran, and he has been with IDOT since 2006.

He had stopped just after midnight Tuesday morning to help a driver whose car had a flat tire. They were in the right lane of the southbound traffic.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

CBS 2’s Suzanne Le Mignot reports that driver, Travis Rhodes, had pulled over after his front right tire blew out as he entered the Dan Ryan near 26th Street.

Before he could even call for help, he saw an IDOT Minuteman in his rearview mirror, coming to assist him.

Rhodes said the minuteman told him to stay in the car, so he’d stay safe while towing the car.

“A split second after he said that, the impact hit. It was terrible,” Rhodes said.

While hooking up Rhodes’ car to be towed, the IDOT Minuteman was hit from behind by a driver in grey-colored passenger car.

“He came to the rescue, and it’s terrible that happened to him,” Rhodes said.

It was likely the car’s side view mirror that hit the minuteman, according to Illinois State Police Master Sgt. Steven Tufenkjian.

“There were a few parts from the vehicle left on the scene,” Tufenkjian said. “We don’t have any license information. We did not have any witness information. The vehicle continued on from the scene immediately after the crash.”

The driver kept going and never stopped.

“That was the crazy thing,” Rhodes said. “You’re going to keep going, not even stop, not even a brake or nothing? Just kept going.”

Rhodes said the driver who hit the minuteman appeared to be speeding.

“He had to be going 80 to 100 [mph], because we didn’t even see the car. We didn’t even see, just … went right past.”

When the minuteman arrived at Northwestern Memorial Hospital, it appeared he only had a fractured right leg, but doctors later downgraded him to critical condition due to internal bleeding, authorities said.

“If anyone out there knows anything about this crash, saw the crash or has any information regarding the crash, or a gray passenger vehicle with damage to the right passenger headlight-taillight assembly area, you’re encouraged to call the Illinois State Police,” said state police Lt. Paul Riggio.

IDOT emphasizes that being a minuteman is not an easy job.

“it’s a very dangerous job. They put their lives on the line every single day when the report to work,” said IDOT spokesman Guy Tridgell. “Last night’s incident was another unfortunate example of the dangers that are involved.”

Rhodes said there’s a slight bend to the road where the crash took place.

“Before all this happened, we were sitting there, and an 18-wheeler was coming fast around. We almost got hit by an 18-wheeler. They couldn’t see the hazard lights. Like, that was crazy,” he said.

Rhodes said the hit-and-run driver did leave something behind: a grey-colored side mirror. He said he hopes that leads to the driver soon.

Meantime, his thoughts are with the minuteman who came to his aid.

“I can’t even get his name,” Rhodes said. “So my name is Travis, and I want to say thank you for, you know, being there to rescue me, and sorry what happened to you. Wish you well”

Tridgell said an average IDOT minuteman tends to about 125,000 traffic calls every year, and take many risks.

The car involved may have been a gray Nissan.

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