The mayor of Waukegan, Illinois, made an emotional plea for residents to stay calm after police opened fire on a car occupied by an unarmed young Black couple, killing one and wounding the other.

Mayor Sam Cunningham said he is close personal friends with the grieving families of the couple shot on Tuesday night in the Chicago suburb, prompting outrage and plans for a large protest on Thursday.

Relatives identified the couple as 19-year-old Marcellis Stinnette, who was killed, and Tafarra Willams, the mother of his baby, who was wounded.

Lake County Coroner Dr. Howard Cooper confirmed Stinnette's identity on Thursday and said preliminary autopsy results indicate he died "from injuries due to gunshot."

"This is tough on Waukegan. This is tough on this community," Cunningham said at a news conference on Wednesday. "I know these families personally."

He said Stinnette was the grandson of Josie Stinnette, a woman he lived across the street from and grew up with. He said he grew up with Williams' mother, Clifftina "Tina" Johnson.

"To be able to speak to them about this, yes, it hurts," said an emotional Cunningham, who in 2017 became Waukegan's first African American mayor. "It just doesn't hurt me, the police department -- it hurts Waukegan, Illinois."

He added: "Yes, I'm nervous. I'm nervous because there's a lot of uncertainty out there, there's a lot of rumors flying around. I'm nervous for Waukegan. We've seen this play out throughout this country. It just rips through communities and it takes years to rebuild."

Since the May 25 death of George Floyd, a 46-year-old Black man who died after a Minneapolis police officer pinned his neck to the ground with his knee, with Floyd heard crying out, "I can't breathe," many protests, including some that turned violent and led to looting or vandalism, have erupted across the U.S.

The Waukegan shooting comes less than a month after no homicide charges were filed in the death of Breonna Taylor involving three white Louisville Metro Police Department officers who opened fire on the 26-year-old Black emergency medical technician in her apartment while they served a no-knock search warrant. A grand jury that heard evidence in the case said it wasn't given the option of filing homicide charges because prosecutors said Taylor's boyfriend fired the first shot.

One of those officers, Brett Hankison, was charged with wanton endangerment for allegedly firing shots that penetrated a wall of Taylor's apartment and entered a residence occupied by a family. Hankison, who has been fired by the police department, pleaded not guilty.

Waukegan is just 15 miles south of Kenosha, Wisconsin, a city that erupted in protests that turned violent following the Aug. 23 police-involved shooting of Jacob Blake, a 26-year-old Black man who was shot multiple times in the back and paralyzed.

Johnson said her daughter, who is expected to survive bullet wounds to the stomach and hand, told her a police officer opened fire on the car she was driving "for nothing" and that Stinnette died in the passenger seat next to her.

"She said, 'Mama, they just shot us for nothing,'" Johnson told ABC station WLS in Chicago. "My daughter said she put her hand up, and if she didn't put her hand up, she said, 'Mama, I would be dead.'"

Waukegan Police Department Commander Edgar Navarro said the shooting unfolded just before midnight on Tuesday when an officer went to investigate a "suspicious vehicle" that fled when he approached.

Navarro said a second officer spotted the car and pulled it over.

"That officer exited his vehicle and the vehicle that he was investigating began to reverse toward the officer," Navarro alleged. "The officer then pulled out his duty weapon and fired into the vehicle that was reversing. Both occupants were struck."

He said the female driver was wounded and the male passenger was taken to a hospital, where he was pronounced dead.

No weapons were found in the car.

Navarro declined to release the name of the officer involved in the shooting. He said the officer who initially approached the car and the one who opened fire have each been placed on administrative leave and that the investigation has been turned over to Illinois State Police.

He said video footage from the officers' body cameras and squad car dash cameras also was turned over to state police, but he declined to say whether any of the footage captured the shooting.

"We're also upset. It is something our community, our police department has great concern over, and it's difficult for all of us," Navarro said.

In a written statement, police officials said that both officers involved in the incident are five-year veterans of the department. Officials noted that the officer who opened fire on the couple is Hispanic and the officer who initiated the suspicious-vehicle investigation is white.

Navarro was forced to give two news conference on Wednesday after the first one, outside the police department, became chaotic when friends and relatives of Stinnette and Williams began interrupting him, yelling, "He's lying!" and, "Why'd you shoot them?"

The second news conference was inside the police station away from supporters of the couple, who organized a march on Thursday from the scene of the shooting to police department headquarters.

Lake County State's Attorney Mike Nerheim said he'll review all the findings of the investigation and decide whether charges are warranted.

"Illinois State Police comes in, they conduct a completely independent investigation. The Waukegan Police Department will play no role in this investigation," Nerheim said.

In 2015, Nerheim, a Republican, came under criticism when he declined to file charges against a white Zion, Illinois, police officer who fatally shot 17-year-old Justus Howell, a Black teenager from Waukegan, in the back. Nerheim said at the time that the officer was justified in using deadly force because a gun was found next to Howell's body.

The shooting led to large protests that continued after Nerheim's decision. In June, protesters demanded Nerheim reopen the investigation, but the prosecutor refused.

Nerheim said he will not make a decision in the shooting of Stennette and Williams until the investigation is complete, cautioning that it could take several weeks.

"My process is, I don't review these cases piecemeal. I do that intentionally. I wait until the entire investigation is done, and then I review everything. So as we speak, I have seen nothing in this case," Nerheim said. "If I determine that a police officer or anybody committed a violation of the law then they will be charged. If I determine that they did not, then they won't be charged and I will release a very detailed statement explaining the law, the rationale for that decision."

He said that in keeping with a policy enacted in 2015, he will release the entire case file, including any video footage, once he renders a decision.

"The important point to make here is that this will take some time. I know this raises a lot of emotions in us as well and we're all upset about this, but I just hope people will stay calm and respect the process," Nerheim said.

Cunningham, a Democrat, pleaded with people calling for justice to wait for the facts to come out.

"If it comes out where there was something that happened, where we did something wrong, we will deal with it," Cunningham said. "I hope this doesn't cause us to be at a point where you distrust the city or the police or each other. I hope it's a time that we can stand together and say, 'We're going to find out the truth, the whole truth and nothing but, and make our decision based on that.'" (ABC News)

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