Toronto police say a man accused of shooting a TTC fare collector during a failed robbery attempt at Dupont Station on Sunday night is responsible for two previous gunpoint hold-ups at the same facility.

At a news conference Monday afternoon, police Staff Insp. Mike Earl said investigators don't know why the suspect, who remains at large, is repeatedly targeting fare collectors at Dupont Station.

"It's something that puzzles us because this is the only collector booth that he's robbed," Earl said at the news conference, where police revealed a link between the incidents and released several surveillance images of the suspect.

The latest incident occurred Sunday when gunshots were fired through a protective glass shield at a fare collection booth, striking a male employee in the neck and shoulder.

Victim expected to recover

The employee, a 10-year veteran of the TTC, is in stable condition in hospital and is expected to recover.

After the shooting, the suspect was chased by a citizen who police haven't been able to locate. Investigators are asking the person to call them to provide a statement.

In the previous armed hold-ups in June and October, the suspect stole an undisclosed amount of cash and no injuries were inflicted to the fare collectors, Earl told reporters.

The images were captured by closed-circuit television cameras during the previous robberies. Police haven't released images from Sunday's incident.

In each case, the suspect wore similar clothing, had his face covered and was carrying a revolver when he approached the fare collector and demanded cash.

A white medical mask covered his face during the robbery in June and he wore a black balaclava during the hold-up in October.

No TTC employee was harmed until Sunday's incident, but there were threats of violence during the previous robberies, Earl said.

TTC launches safety review

Sunday's shooting immediately raised questions about the safety of the TTC fare collectors, prompting TTC brass to call an emergency meeting Monday morning to review the incident and discuss what, if any, security measures can be improved or added.

After the meeting, Andy Byford, the TTC's interim chief general manager, told reporters the transit agency is considering its options and will look at the design of the glass protecting its fare collectors.

Byford told reporters the glass isn't bullet-proof but it is reinforced.

He said surveillance cameras recorded the shooting and an alarm was activated by staff following the incident.

Byford said he doesn't think there is anything wrong with the design of Dupont Station, where various security-related incidents have occurred in recent years.

Byford later spoke to reporters again at the police news conference, where he said the TTC didn't fail to act after the earlier robberies at Dupont Station.

He said the TTC has responded to robberies by installing cameras that point towards collection booths, making sure booths contain limited amounts of cash, and installing silent alarms, like the one activated after Sunday's shooting.

Presto cards

After the meeting, TTC chair Karen Stintz said the commission is already implementing Presto swipe cards that will help to improve safety.

In response to so-called "smart cards," Byford said he would welcome anything that would reduce the risk for staff.

"I think it is important that we look at all events that happen and not knee-jerk into anything," Byford said.

City Coun. Doug Ford said it's up to the TTC to decide how to improve security, but suggested it may be time to move to a fully-automated fare collection system that doesn't require collectors.

Ford said New York City uses such a fare collection system.

An average of two TTC employees are assaulted at work every day, Byford said.

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