Philadelphia police announced Tuesday the officer who shot and killed an armed 12-year-old boy who allegedly shot at plainclothes officers last week will be suspended with intent to dismiss. Philadelphia Police Commissioner Danielle Outlaw calls the incident a tragedy on all sides with no winners.

Police initially said four plainclothes officers were in an unmarked police vehicle and spotted Siderio with a gun that was later found to be stolen.

Outlaw confirmed Tuesday the vehicle’s police lights were activated when moments later, she says, the 12-year-old fired at the officers, CBS Philadelphia reports.

Outlaw says as Siderio ran, an officer fired his gun, striking Siderio in the back, killing him and violating the Philadelphia Police Department’s use of force directive.

On Monday, the four police officers involved in the shooting were faced with a lawsuit from the boy’s family. The three other officers are on administrative leave.

Philadelphia's progressive district attorney, Larry Krasner, says the incident is being investigated by the police department as well as the DA Office’s Special Investigations Unit.

“The death of a child is always a tragedy, and in this instance, a factually complex and deeply troubling one based on preliminary investigative information,” Krasner said in a statement. “As prosecutors, we have a duty to seek justice by following the facts and law, wherever they lead us. Philadelphians are owed a comprehensive and transparent accounting of all activity surrounding the circumstances of young Thomas Siderio’s death and an unbiased and thorough investigation. When it is appropriate for us to do so, we will disclose findings of our currently active investigation and decision on whether or not to pursue any criminal charges.”