The blood-spattered man climbed atop a Mercedes-Benz at a stoplight in downtown Sydney and held a knife in the air. He’d already stabbed one woman at a nearby hotel, police later said, and tried to attack others in the busy commercial district on Tuesday.

That’s when a bystander, armed only with a wooden chair, jumped into action. Others quickly helped. Soon, the civilians subdued the attacker, pinning him to the pavement with chairs and a milk crate until police arrived.

“They were significantly brave people,” New South Wales Police Superintendent Gavin Wood told reporters at the scene. “To approach a person with a mind set of obviously what this person did, with clear evidence of a stabbing previously, these people are heroes.”

Police have identified the suspect as Mert Ney, 21, the Sydney Morning Herald reported. Authorities told the newspaper they do not consider the attack terrorism-related, but they are investigating. Ney has a history of mental health issues, the Morning Herald reported.

“Information was found on him that would suggest he had some ideologies related to terrorism … but he has no apparent links to other terrorist organisations,” NSW Police Commissioner Mick Fuller told the Morning Herald. “It is not currently classed as a terrorist incident. … As [the] investigation continues, we will reassess that.”

Ney is in police custody. The woman who was stabbed at the hotel is expected to survive, police said, but investigators later found another woman dead in a nearby apartment. They’re trying to determine whether that death is related to the stabbing.

It’s unclear what set off the attack, which Wood called “unprovoked,” noting that the attacker “stabbed an innocent woman for no specific reason.”

Police first received a call around 2 p.m. local time Tuesday that a man armed with a knife was walking down York Street in the city’s Central Business District, more than a mile south of the Sydney Opera House. As authorities were en route, more calls came in that the man had stabbed a woman in the back at a hotel.

Before police could arrive, the man tried to stab more people in the street, Wood said. That’s when bystanders jumped into action.

“I ran outside and saw people grabbing poles and bats from a firetruck and started to chase [the man] up the street,” a witness told 10 Daily.

In a video captured by bystanders, the suspect hops on a car idling at a stop light. The man driving that car, an Uber driver, later told the Morning Herald that he hit the gas to get him off his roof.

“I froze for probably a split second,” he told the paper. “Then, I quickly accelerated so he could get off the car. … He was completely fearless. It was a scary moment.”

That’s when a bystander holding a chair chased the man into an intersection, where he began yelling, “Shoot me! … Shoot me in the f---ing head!”

Once the crowd had pinned the knife-wielding man down, his arms and shirt covered in blood, others tried to understand what was happening.

“He stabbed a chick in broad daylight,” one bystander exclaimed.

When police arrived, they arrested the man. About an hour later, authorities discovered a body.

“Inquiries are underway after the body of a woman was found in a unit on Clarence Street in Sydney at 3:15 p.m.,” an NSW Police spokesperson told The Washington Post. “Officers from the Sydney Area Command are on scene and will conduct inquiries into whether the incident is linked to an earlier stabbing at a hotel on the corner of Clarence and King Street.”

Police credited the bystanders who took on the attacker, with Wood calling them “heroes.”

“I want to acknowledge those members of the public who got involved. They were brave and I can only use that word seriously,” he told reporters. “These people, these members of the public, going about their daily business have jumped into a situation that was extremely dangerous, extremely hostile.”

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