By CBS3 Staff

PHILADELPHIA (CBS) — A fired Philadelphia police officer is now under arrest for his role in the violent assault of a woman and her toddler during unrest in West Philadelphia following the 2020 fatal police shooting of Walter Wallace Jr.

District Attorney Larry Krasner said Thursday that 42-year-old Darren Kardos has been charged with aggravated assault and other charges.

READ MORE: 2 Montgomery County School Districts To Require Masks Again Due To County's COVID-19 Level

Officials say the arrest follows an 18-month investigation.

“In order to do a thorough investigation, you have to do a lot more than look at body-worn camera,” Krasner said. “You also have to try to do interviews with witnesses, who may or may not have fifth amendment rights. I could go on.”

Investigators say they began looking into possible police misconduct after cellphone video captured social unrest in West Philadelphia in October 2020. It followed the fatal police shooting of Wallace Jr.

The district attorney says cellphone video later showed several police officers surrounding an SUV, breaking in the windows and then pulling the driver out and beating her. The victim was later identified as Rickia Young.

“She was struck by fists, batons and a number of unknown objects,” Krasner said. “And she was maced.”

At the time, Young was driving with her 2-year-old son and 16-year-old nephew. Her lawyers say she had just picked up her nephew in West Philly, who was fearful of the growing tension between police and those protesting the killing.

Her SUV got caught in the middle of the ruckus and that’s when her lawyers say responding police bashed her windows in, got her on the ground and beat her with their batons — and then arrested her.

Philadelphia police say two officers were fired as a result of this incident. In addition, 14 other officers are awaiting disciplinary hearings.

A photo of a police officer holding the woman’s child then went viral after it was posted online by the National Fraternal Order of Police with a caption claiming officers saved a child.

Krasner called that social media post a fabrication.

READ MORE: 5-Year-Old Boy Injured In North Philadelphia Shooting, Police Say

“The FOP later deleted this false, inflammatory, possibly even defamatory post, but to put it mildly, this is shameful,” Krasner said.

Kardos is charged in connection with the mother’s assault.

“The law applies equally to everyone and this office is going to be evenhanded and fair and follow the facts and apply the law to police in the same way that we apply it to everyone else,” Krasner said. “I don’t think there is a good, hardworking, decent police officer in the United States much less in Philadelphia who thinks it’s a great thing to brutalize a mother.”

The City of Philadelphia reached a $2 million settlement with Young in September 2021. The incident with police left Young bloodied, her car bashed in and landed her in jail, separated from her toddler.

Young’s lawyers, Mincey Fitzpatrick Ross, LLC, say this is the first time the city has paid a settlement this large for a non-fatal incident.

Speaking Thursday after the announcement of the charges, Young recalled the terrifying moments that were captured on cellphone video.

“I’m still in shock. What you did to me in front of my son was not acceptable,” Young said.

Young hopes other officers involved in the incident face charges too.

“I’m happy that it was recorded to show your true colors,” she said.

Kardos was one of two fired cops from that incident.

It’s not clear if any other officers could face charges.

MORE NEWS: EXCLUSIVE: Teen Pilot Who Landed Plane On Bridge In Ocean City Shares How He Survived New Mexico Plane Crash

CBS3’s Matt Petrillo contributed to this report.