Questions are being raised about just how effective the emergency buttons inside Toronto's subway system are, after a social media post that suggested witnesses to an assault tried to push for help, but that none of the buttons appeared to be working.

Tyler Kyd had just gotten off the train at Sherbourne station after work at about 3 p.m. last Thursday, when he spotted a man on top of a teen beating him.

"There was this gentleman on top of this kid, just pummelling him and yelling that he had tried to steal his phone, or had stolen his phone," Kyd told CBC News.

Kyd intervened with another bystander. They managed to split the pair up before Kyd pushed one of the nearby emergency buttons for help.

But when he pushed it nothing happened. He tried another button, and still nothing.

'We were looking for security'

Another person ran down to the subway platform and pushed two buttons there before coming back up the stairs to tell Kyd there was no response.

"The scary thing was we were looking for security, any sort of help really to come and deal with situation before it got out of hand again. And we were hitting security buttons and none of them were working in the area," he said.

Kyd said he and others stuck around to keep the two apart and that it was about 20 to 30 minutes before any help arrived. Video taken by Kyd and posted to social media shows a young man with cuts and scrapes to his face as a pair of TTC transit enforcement officers arrest another man.

CBC News is not posting the video because it depicts an underage victim.

Tyler Kyd had just gotten off the train at Sherbourne station after work at about 3 p.m. last Thursday, when he spotted a man on top of a teen beating him. (Grant Linton/CBC)

Toronto police confirm a man in his late 30s, was charged with robbery and assault causing bodily harm in connection with the incident.

Const. David Hopkinson said the victim was charging his phone inside the subway station when the suspect, who was sleeping nearby, awoke. Hopkinson said the suspect spotted the phone, claimed it was his and grabbed it. When the victim tried to stop him, police say, the suspect began beating him.

The Toronto Transit Commission says the collector in the station at the time had already received a call through the button, which is why transit enforcement officers made their way to the scene.

TTC acknowledges 'frustration' with system

Sherbourne subway station has four such buttons: one inside the turnstiles, one outside and two on the subway platforms.

"It's similar to a phone system. You pick up your phone — you don't have call waiting — you get a busy signal," spokesperson Stuart Green said.

The trouble is if a button is pushed while the collector is already responding to another button push, it won't go through — which could pose problems if there are multiple emergencies underway at the same time. On top of that, Kyd says there was no sound or signal that any other call was underway.

It's a situation Green acknowledges isn't ideal.

If a button is pushed while the collector is already responding to another button push, it won't go through, TTC spokesperson Stuart Green says. (Paul Borkwood/CBC)

"I absolutely understand the frustration. You think you're doing the right thing by pushing the button and you're not getting a voice back," he said. "It would be helpful to know that someone is already on the call with somebody."

"Right now, our system doesn't allow for a priority so if there was a second incident, they wouldn't be alerted to that," he told CBC News.

Agency will consider fix

Kyd says he didn't see anyone else pushing for help at the time of the incident, but has concerns either way.

"There's a safety button on the wall and everybody sees it walking by," he said. "Then the one time you need it, there's nothing."

Green says the transit agency is in the midst of upgrading to a digital system and will consider a fix.

In the meantime, he says the existing system is regularly checked and tested once a month.

The agency also says it has been installing more security cameras at its stations and bringing staff outside of collector booths as they move to a Presto-based system, which could help cut down on the wait time for help to arrive.

For Kyd, the change can't come soon enough.

"The thing that scared the crap out of me is that my girlfriend gets off at that station and goes out the back end as well, ... And it's like, 'What if she was in there running for help and there's nothing?'"