A 20-year-old man is wanted on a charge of attempted murder after a 35-year-old man was stabbed in the neck aboard a subway train Wednesday night in what is being described as an unprovoked attack.

The stabbing occurred on a train that was heading south on the Yonge-University-Spadina line approaching Davisville Station at about 10:20 p.m.

Before the knife attack, the suspect walked through the train and bothered passengers, and he eventually began to talk to the victim, who was sitting alone and keeping to himself, a police spokesman told CP24.

Moments later, the victim was slashed across the neck when he stood up and told the suspect to leave him and others alone, police said.

Police described the attack as being "out of the blue."

After the stabbing, the passenger assistance alarm was activated and the train stopped at Davisville Station, where it was held until police and paramedics arrived. The suspect exited the train and took off.

The victim was rushed to hospital, where he is being treated for serious injuries.

The stabbing occurred on one of the TTC's newer trains, which feature open gangways that allow passengers to move freely from one end to the other, and are equipped with surveillance video systems.

Police release surveillance photos

Investigators identified a suspect after releasing several surveillance images Thursday. The images were recorded on the subway train and in a subway station.

In one of the photos, the male is holding a knife in his right hand, along with a white plastic bag.

Police are now looking for 20-year-old Toronto resident Cassim Celani Cummings.

In addition to attempted murder, Cummings is wanted for aggravated assault, assault with a weapon, failing to comply with a probation order and two other weapons offences, police said.

Police said Cummings is considered violent, armed and dangerous, and if he is located people are asked not to approach him but to call 911.

Anyone with information about the case is asked to call investigators at 416-808-5300 or Crime Stoppers at 416-222-TIPS (8477).

TTC responds to security fears

Despite the incident, the TTC is assuring people that Toronto’s public transit system is safe and violence on TTC property is rare.

"The TTC is one of the safest transit systems in the world," said TTC spokesman Brad Ross. “Unfortunately, individuals will do things for reasons unknown and that’s where the police come in."

In response to questions about the state of security on TTC vehicles, Ross said it is not possible to put a police or transit enforcement officer on every subway train, calling such a measure a waste of resources.

“Those kinds of things cost a lot of money and to spend those kinds of resources on such rare occurrences, we’d be better off spending that money elsewhere,” Ross told reporters. “That’s why we have security systems on the trains, on our vehicles, so that police can apprehend suspects when these things occur.”

Ross asked riders to activate the passenger assistance alarm if they witness a crime, including vandalism, harassment or threats, or physical violence.

Ross urged people to call police if they have any information about the suspect.

“A stabbing on a subway train is extremely rare, so clearly we’re dealing with an individual here who needs to be caught and, perhaps, needs some help, I don’t know,” Ross said.

Ross said the surveillance images are being shared with TTC employees, who are on the lookout for the suspect, should he return to TTC property.

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