CHICAGO (CBS) — Illinois State Police on Monday afternoon were trying to figure out how two wrong-way drivers ended up on the Eisenhower Expressway – causing crashes that left a total of five people dead.

Both drivers were headed outbound in the inbound lanes. One got into a head-on crash off Des Plaines Avenue in Forest Park, while the other crashed near the Jane Byrne Interchange just west of downtown.

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As CBS 2’s Tara Molina reported, Illinois State Police would only say Monday afternoon that they are investigating. Thus, it is not clear where the drivers got on the wrong way, what ramp or entrance was used, and what signage is posted there.

The mangled aftermath of the first wrong-way crash on the Eisenhower in Forest Park, just after 1:15 a.m., was a tough scene to take in. Illinois State Police said someone was driving a black Honda the wrong way on eastbound I-290 in Des Plaines and hit a silver Infiniti.

The cars caught fire due to the impact of the crash, and heavy smoke could be seen around the area of the crash.

Police said the woman driving the Honda and the 21-year-old woman from Melrose Park driving the Infiniti were killed in the crash. A 26-year-old man from Berwyn, who was a passenger in the Infiniti, was taken to the hospital with non-life-threatening injuries.

And just about 20 minutes later, several miles away, the driver of a black Land Rover drove down Interstate 290 – again west in the eastbound lanes – hitting a Ford Edge in the right lane. The Ford Edge spun out and hit a Ford Escape.

Three people were killed in the crash, including the driver of the Land Rover, the 51-year-old man driving the Ford Edge, and a 24-year-old woman who was a passenger in the Ford Edge.

The driver and two passengers in third car — a 23-year-old woman and two 26-year-old women — were rushed to the hospital, without life-threatening injuries.

Late Monday afternoon, Illinois State Police would not say if the two crashes have more in common than timing and location – or what is being done to prevent another.

“Fatality rates? Wrong-way crashes, much higher than the others,” said Dr. Huagao Zhou, a civil engineering professor at Auburn University.

Dr. Zhou has studied wrong way crashes for years, and prepared a study here in Illinois on reducing them. We asked him about the crashes early Monday morning on the Eisenhower.

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“This is a very typical pattern compared to the history of fatal crash data,” Zhou said.

That is because of when and where these wrong way crashes happened – early in the morning on a major roadway.

Dr. Zhou said about 60 percent of wrong way drivers are under the influence.

That is backed up by a recent AAA study that found the odds of being a wrong-way driver increase with alcohol, age, and driving without a passenger.

It remained unclear late Monday if alcohol was a factor in these recent crashes.

As for how drivers can protect themselves, Zhou said that can be difficult – so awareness is key.

“Due to nighttime, you may not be able to judge the distance because the approaching speed is much faster,” Zhou said.

We have confirmed a third fatal wrong way crash Sunday morning on Interstate 57 at 183rd Street in the southern suburbs.

Again, we are still waiting on more information from ISP as they investigate the two crashes here. ISP released this statement:

“The two fatal traffic crashes that occurred early this morning are under investigation. At this time, the only available information is what was disseminated in both press releases. The Illinois State Police would like to remind motorist to remain alert, avoid distractions from outside and inside of the vehicle, and obey the speed limit. Our priority is to ensure all motorist drive safely.”

Meanwhile, we had to file a public records request to get information on other wrong way crashes across the state, and specifically in the Chicago area. That information was not available late Monday, but the Illinois Department of Transportation did release this statement:

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“Because safety is always our No. 1 priority, IDOT constantly reviews and analyzes crash data to identify possible safety concerns and countermeasures. Wrong-way driving has been studied by IDOT previously, resulting in improvements at multiple locations in the Chicago area. New strategies and approaches to alert traffic to wrong-way drivers and prevent such incidents are being developed and tested all the time. The department continues to monitor and investigate.”

Tara Molina