It was previously known that Officer First Class Jacai Colson had been killed by friendly fire.
"The shot that struck and killed Detective Colson was deliberately aimed at him by another police officer. It's another tragic dimension to this unfolding story," Prince George's County police Chief Hank Stawinski told reporters.
He stressed how chaotic the situation was and that he does not believe any malice was involved on the part of the officer who fired the weapon.
The chief stopped short of speculating what that officer may have believed about Colson in the moment.
Colson was in plain clothes with no bulletproof vest when he jumped out of his unmarked car Sunday to confront a gunman outside a police station. Three other officers returned fire.
"The environment was incredibly chaotic. We had officers under fire immediately, trying to seek cover," Stawinski said.
"There's no intention, as I have seen the facts and as they have been explained to me, to indicate any malice or anything along those lines."
Brothers recorded shooting
Michael Ford, 22, is accused of initiating the shootout with police. Authorities have said his brothers, Elijah and Malik Ford, watched and filmed as he used a .40-caliber handgun to open fire on officers outside the station, as well as at an ambulance and random people's cars.
Elijah, 18, and Malik Ford, 21, each face 10 charges, including first-degree assault, attempted murder, and conspiracy to commit murder, said State's Attorney Angela Alsobrooks. Both are being held on no-bond status.
Michael Ford, who suffered what's believed to be nonlife-threatening injuries, faces 25 counts, Alsobrooks said. He is also being held without bond.
Michael Ford discussed with his brothers a plan to "engage police in a shootout," according to charging documents filed in district court. His brothers drove him in a red Honda Accord to an intersection near the police precinct, dropped him off so he could approach the precinct on foot, drove to a nearby side street and began recording the incident, the documents allege.
Soon after the shooting began, Michael Ford took cover behind a police van and police officers asked the brothers where he had gone, the complaint says. Malik Ford shouted back that he did not know, despite Michael Ford being visible, thus allowing Michael Ford to continue his attack, police say.
The entire incident was captured on cell phone and surveillance footage.
Officer was a 'hero'
Colson, a four-year veteran of the Prince George's County Police Department, would have celebrated his 29th birthday this week.
He was an undercover narcotics officer and fondly remembered by his friends and colleagues.
Colson was a "brother, friend, police officer, and a hero -- not only to the Prince George's County Police Department, but to every citizen in Prince George's County," Fraternal Order of Police Lodge 89 President John Teletchea said.
Teletchea said the Boothwyn, Pennsylvania, native was a personal friend, one with an infectious smile and tremendous personality.
"Jacai could light up a room. He lit up everybody's life he touched," Teletchea said Monday.
"He made a decision several years ago to make a difference in the world when he joined the Prince George's County Police Department. He made a difference every day he was here, and he made the difference and saved lives yesterday."