FOREST PARK, Ill. (CBS) — A man was charged Tuesday afternoon in a mass shooting that left four people dead on a CTA Blue Line train in west suburban Forest Park the day before.

Rhanni Davis, 30, of Chicago, was charged with four counts of first-degree murder, according to Forest Park police, who announced charges Tuesday evening along with Cook County State’s Attorney Kim Foxx and Chicago Transit Authority President Dorval Carter.

All four victims were passengers on a Blue Line train as it was headed into the Forest Park terminal when they were shot shortly before 5:30 a.m.

Police said three victims were found dead at the scene. A fourth victim was taken to a local hospital, where they died. Officials had identified two of the victims as of Tuesday afternoon—Simeon Bihesi, a 28-year-old man, and Adrian Collins, a 60-year-old man.

Collins died of a gunshot wound to the abdomen, while Bihesi died of multiple gunshots.

The Cook County Medical Examiner’s office said one of the other two victims was a 52-year-old man and another was a 64-year-old woman.

CTA security and Forest Park Police found the suspected shooter using surveillance video. The suspect was located on a CTA Pink Line Train and taken into custody later Monday morning. 

A weapon was recovered. The gun was a 9mm Glock 43 with six rounds, according to Forest Park police Lt. Daniel Pater, who is in charge of the investigation unit.

Police said the shooting appeared to be an isolated incident and that the suspect did not seem to know any of the victims, who all appeared to be sleeping while riding the train. Police also said it did not appear that the shooter tried to rob the victims and that the attack was completely random.

“We should be free to ride the train, to do yard work, gather with friends of a front porch,” Foxx said. “Public transportation should be a safe space for everyone.”

Foxx emphasized that it was only two weeks ago that the Chicago shined—and hosted over 50,000 people—for the Democratic National Convention.

Foxx added that there are no answers yet as to the motive for the “heinous, heinous act,” and she fears there never will be.

Meanwhile, Carter said CTA employees immediately began assisting police as soon as they learned of the horrific crime—helping in such tasks as reviewing security camera footage. He also focused the CTA’s own emphasis on safety.

“To our riders, we want you to know that we hear you, and we understand your concerns about safety. The men and women of the CTA are united in our commitment to ensure that we’re doing everything in our power to protect our riders, as well as our employees,” Carter said.

Carter said he could not speak to whether the four people who were shot and killed on the train were homeless.

“What I can tell you is that on the issue of homelessness itself, we have engaged and provided more resources to support people who are homeless on CTA than ever in the history of our agency,” he said.

This effort includes partnering with social agencies whose representatives are on the system every night to provide the unhoused options other than sleeping on the CTA.

But Carter added that the CTA alone cannot solve crises such as homelessness and addiction.

Just last week, the CTA announced it was rolling out a pilot program involving AI gun detection technology on its system. Carter said the program was not a factor in this case.

Entire mass shooting was caught on camera

Cameras on the trains captured everything that happened in the course of the mass shooting. CBS News Chicago is told the video is shocking, and it will be used as evidence.

“It’s unusual to have a multiple killing on a CTA train,” said CBS News Chicago Legal Analyst Irv Miller. “The CTA has more cameras—high-definition cameras—than any other place in the in the entire county, so somebody had to basically say, ‘I’m going to do this, and I don’t care if I get caught.”

Davis has been arrested several times since 2014—and he was sentenced to two years’ probation for a misdemeanor battery charge that year. He also pleaded guilty to disorderly conduct in 2020.  

If Davis is convicted on four counts of first-degree murder, the only sentence that applies in Illinois is natural life in the penitentiary without parole. Miller explained that the question of mental state is really the only defense that applies in Davis’ case.

“There are defenses under the law, and one of the defenses that popped into my mind on a case like this is the defense of insanity. If that’s raised, it doesn’t make any difference if it’s on a videotape or not. The question is the person’s mental state—was this person able to appreciate the criminality of their conduct?” Miller said. “So when you when you shoot four people when they’re sleeping—and it’s caught on videotape—frankly, there’s not many defenses available to you.”

The mass shooting happened as CTA President Carter was already under fire—with calls for his resignation having made headlines back in May. Some Chicago alderpeople’s disdain for Carter has been renewed in light of the murders.

Meanwhile, the Forest Park Blue Line terminal has been an area of concern for law enforcement for some time. Forest Park village leadership said problems at the terminal go back years—and have only gotten worse.

Foxx said Davis will appear for a detention hearing at the Maybrook Courthouse in Maywood at noon on Wednesday.