Toronto police have chased down many leads, but have still not been able to find the person who shot a TTC collector at Dupont station a year ago.

Staff Insp. Mike Earl reminded reporters on Tuesday afternoon that the same suspect had actually robbed the subway station on two prior occasions before the shooting on Feb. 26, 2012.

But no shots were fired until the incident on a Sunday night last year when the on-duty collector was wounded.

"The collector had no cash, or provided no cash to the suspect, at which time the suspect turned, commenced to walk away from the victim and then turned and fired three shots," he said during a news conference at police headquarters.

Earl said the TTC collector was hit in the bicep and the neck.

The suspect then fled the station and went to a parking lot at Spadina Avenue and Macpherson Avenue and entered a silver vehicle.

Earl said the public has provided many tips to police, but none have resulted in an arrest.

"We've interviewed several people, we have traced down numerous leads and at this point we are no further ahead in the investigation," Earl said.

Additionally, police have never been able to make contact with a male witness who was seen chasing the suspect on Spadina Avenue after the shooting.

Male or female behind mask?

Police still do not know whether the suspect is a male or a female.

But police say the shooter is between 5'2" and 5'5", contrary to the prior belief of investigators that he or she was several inches taller.

Earl said the gun-toting suspect has "a stocky or chunky build" and has consistently worn a mask during the robberies.

In all three incidents, the handgun was held in the suspect's left hand.

Earl said it is concerning to police that this person was quick to fire upon a TTC collector without any provocation.

"We take this case very seriously," he said.

"The hold-up squad wants to solve this case, it’s one of the most important cases we've had in years and we really want to put it to rest."

Andy Byford, the TTC's chief executive officer, said the staff member who was shot has physically recovered, but has yet to return to work.

"I never want to see that happen to a member of my staff again and there is still someone out there at large who has committed this heinous assault," he said Tuesday.

Byford said the $25,000 reward remains in place for any information that leads to the arrest and conviction of the person who shot the TTC collector.