JACKSON, Miss. (AP) — A mother says she wants justice for her 17-year-old son who died when a police SUV ran over him in the small Mississippi Delta town where he lived.

Kadarius Smith and one of his cousins were out walking March 21 when a Leland Police Department vehicle chased them and fatally struck Smith, said his mother, Kaychia Calvert. He died later at a hospital.

“He still had his whole life ahead of him,” Calvert told The Associated Press. “They just took his life away from him.”

Police referred all questions to Josh Bogen, attorney for the city, and he said officers were responding to a call about an assault in progress. He could not confirm if Smith was a suspect.

Bogen said it was an “accident” that the vehicle struck Smith.

“The idea that the police officer purposely ran over the alleged victim is a complete absurdity,” Bogen told the AP.

Smith was Black. Bogen said police told him that at least one responding officer involved was also Black. Bogen did not offer any other details.

The AP requested copies of police reports and police camera footage from Bogen, but he said they are not available during the investigation. The AP filed a formal request for the documents Friday.

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Calvert described her son as “a loving, caring person” who was smart, independent and outgoing. He was in 11th grade and played on the Leland High School basketball team. Leland is in the flatlands of cotton and soybean country and has a population of about 3,900. It is about 110 miles (177 kilometers) northwest of Mississippi’s capital city of Jackson.

Smith’s family has retained civil rights attorney Ben Crump and they are demanding that the officer who drove the vehicle be fired, and that unedited police camera footage be released.

“It is unconscionable that an officer would fatally run over a teenager who was running away from them,” Crump said.

Bogen said “there’s not a word of truth” to Crump’s statement.

Calvert said her son’s cousin told her that he “heard a loud boom” and then saw the SUV leaning like it was about to flip. She said he told her that the SUV landed on its wheels, ending up on Smith’s body.

“My son didn’t do anything wrong,” Calvert said. “The police officers, they just saw two boys walking home, and that’s how it got started. My son — he’s not a thug.”