CHICAGO (CBS) — CBS 2 News has learned that Jason Nightengale, the man who police say killed three people and injured four on a shooting spree that spanned the city this weekend before he was shot dead by Evanston officers, has a criminal history spanning more than a decade.

Meanwhile, as CBS 2’s Steven Graves reported Sunday night, social media posts show disturbing and troubled moments before the shooting spree on Saturday.

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Nightengale, 32, is accused of killing three people on Chicago’s South Side on Saturday.

Police said he first shot and killed University of Chicago Ph.D. student Yiran Fan, 30, in the parking garage of the Regents Park building, at 5045 S. East End Ave. in the Indian Village section of the East Hyde Park-Kenwood community. He then shot and killed security guard Aisha Johnson, 46, and wounded a 77-year-old woman who was getting her mail, at The Barclay condo building, on the next block north at 4946 S. East End Ave., police said.

After stealing a man’s car keys at gunpoint on the 19th floor of an Indian Village building, police said Nightengale took off to a convenience store on Halsted Street near 93rd Street in the Brainerd neighborhood. Surveillance video showed him coming up behind customer Anthony “A.J.” Faulkner at the counter and shooting him.

Nightengale was later seen taking the store’s cash. He also shot and critically wounded an 81-year-old woman in the store, police said.

Police said Nightengale then shot and critically injured a 15-year-old girl who was in a car with her mother in the 10300 block of South Halsted Street, then shot at, but did not strike, police officers who were on the scene investigating his earlier shooting at the convenience store, before heading north all the way to the Chicago-Evanston line.

There, he announced a robbery and fired a shot at a CVS store at Howard Street and Asbury Avenue – the Evanston extension of Western Avenue – and then took a woman hostage and shot her at the IHOP across the street. The murder spree did not end until Evanston officers shot him dead in a dollar tree parking lot just to the east.

Nightengale’s personal Facebook revealed a series of disturbing videos in the days and hours leading up to the rampage. He threatened to kill people and even threatened to blow up the community in one video, showed a gun in another, and engaged in random outbursts.

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Nightengale also has a criminal history that dates back years. Cook County court records detail charges and arrests starting in 2005, for drug possession, theft, trespassing, aggravated assault, and domestic battery.

The latest was in 2019, when paperwork shows he violated a protective order. That case closed in July.

Nightengale’s LinkedIn page says he has since been self-employed. In past jobs, he worked as a janitor, a security guard, and a doorman – the same profession held by Aisha Johnson, the woman he is accused of killing in Indian Village.

Officers in Evanston closed Nightengale’s story with a picture of the gun they believe he used in the deadly rampage.

CBS 2 was still trying to determine Sunday night whether Nightengale legally owned the gun.

Graves did reach out to two family members of Nightengale’s by phone. Both hung up on us.

Late Sunday, police were still searching for a motive.

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