Toronto police have offered a $50,000 reward for information that leads to the arrest and conviction of those responsible for shooting and killing 18-year-old Yusuf Ali in a Regent Park alleyway one year ago Tuesday.

At a news conference at 51 Division Tuesday, Det. Sgt. Tam Bui said Ali was walking with two of his friends near Queen and Parliament streets at 2:45 p.m. on Oct. 6, 2014, when he was shot in the back multiple times in an alleyway.

The exact point where he was shot is located near Creemore Avenue and Sydenham Street, Bui said. Several individuals have come forward, but others have not.

“There are other witnesses who were in the area who we believe have material information about the shooting, who left the area before police could speak to them,” Bui said.

He added that police chief Mark Saunders has authorized the $50,000 reward, since all other police leads have failed to identify the shooter.

Bui said the suspect followed Ali “through several different laneways” for at least five minutes, in a “very determined” fashion, before opening fire. He added the firearm used in the killing is linked to one other offence that occurred somewhere in Toronto.

The suspect is described as a man in his 20s with light brown skin, standing more than six feet tall with a lean build, Bui said. The suspect was wearing gloves, a hood and some sort of mask over his face when he opened fire on Ali.

Witnesses and surveillance camera footage suggest the suspect was dropped off on Parliament Street, south of where the shooting occurred, in a newer-model silver car and driven by an unknown person.

“People in this community of Regent Park have information that is material to identifying and apprehending the person who is responsible for this,” Bui said.

Despite the determined behavior of the suspect, Bui said investigators aren’t certain what motivated the killing and are “being open minded about” whether the killing was related to any gang activity.

Bui said he was willing to accept information anonymously and through Crime Stoppers. The reward will be paid to a source willing to testify at trial, Bui said.

“To shoot (Ali) in the back multiple times, kill him in front of witnesses around the corner from a school in broad daylight, that individual is a danger to the public, a danger to this community of Regent Park,” Bui said. “The family deserves some justice, the community deserves some closure.”