ROCHESTER, N.Y. — District Attorney Sandra Doorley announced that the grand jury has indicted Kelvin Vickers, the man accused of killing a Rochester police officer, with 8 charges.

The most severe charge is aggravated murder, for the fatal shooting of Officer Tony Mazurkiewicz. The charge carries a sentence of life without parole if convicted. Vickers is also charged with two counts of assault for the shooting of Officer Sino Seng and 15-year-old Tamaia Walker.

Doorley said the officials are trying to have Vickers appear in front of a judge for arraignment by the end of Wednesday.

Here is the list of charges:

Attempted Aggravated Murder
Murder in the 2nd Degree
Attempted Aggravated Murder
Attempted Murder in the 2nd Degree
Two counts Assault in the 2nd Degree
Two counts of Criminal Possession of a Weapon

Doorley announced the grand jury's decision at a press conference on Wednesday. RPD Chief David Smith, Mayor Malik Evans, and County Executive Adam Bello also attended.

Evans said the indictment is a step toward justice. "I want to thank the district attorney for her work in making sure that officer Mazurkiewicz's life will not be lived in vain," he said.

Vickers, 21 of Massachusets, is accused of shooting the two RPD Officers and Walker during an ambush on July 21. Police said they found Vickers shortly after the ambush hiding in the second-floor crawl space of an abandoned house and took him into custody.

The last known address for Vickers is in Brockton, a suburb north of Boston, which is 400 miles from Rochester. Doorley said she couldn't comment on why he was in Rochester.

RELATED: What we know about the killing of Officer Mazurkiewicz and the man charged

Vickers has had a long history of criminal convictions. He was released from a Massachusetts maximum security prison on May 24 after serving a three-year sentence for a gun possession crime. He was not on parole or supervision after he was released.

Police said Vickers was 12 years old when he faced charges of assault and battery on an officer. Before his 18th birthday, he would be charged with burglary-related offenses, strangulation with a deadly weapon, assault with a deadly weapon, and two separate possession of firearms offenses. When he was 18 he was convicted of possessing an unlicensed firearm.

Kelvin Vickers arraignment will be next Wednesday, August 10 at 9:30 a.m. in front of Judge Julie Hahn. Both Hahn’s chambers and the court clerk's office confirm the date and time.