Transcript for Onlookers pin down knife-wielding man in Sydney
We're going to go overseas now to a heroic takedown in Sydney, Australia. A knife wielding man going on a stabbing spree, attacking two women before hero bystanders jumped in to take him down. Reporter: An extraordinary scene right in the center of Sydney and some extraordinary bravery from members of the public who took on this attacker. This morning, dramatic footage showing a man wielding a bloodied knife running through central Sydney. Despite the risk, brave onlookers taking him down. Authorities say the 21-year-old alleged attacker killed one woman and stabbed another as he charged down the crowded street, jumping on the roof of a car, streaming at onlookers, shoot me, shoot me. Three British men helped stop his rampage. I don't know whether it's an instinct thing but we were trying to steer this guy from doing anymore. My brother and I ran across here. These boys followed and we managed to get a grip along with another guy and restrained him fully. That was significantly brave. A person with the mind-set of what this person did with clear evidence of a stabbing previously, these guys are heros. Reporter: Authorities say the alleged attacker acted alone and may have recently come from a mental health facility. Those young men say the only thing that went through their minds was, you've got to help people. I'm sure everyone in Sydney is ad they did. Incredible pictures. James, thank you.
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