Messages were sweeping across Sydney within minutes of the attack at Bondi Beach.
Parents messaged their children and teenagers, who had been enjoying a late afternoon swim at Bondi.
Witnesses said police were on the scene quickly, and the streets of Sydney's eastern suburbs were full of police cars and ambulances on their way to Bondi.
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When we arrived, there were still dozens of people processing what had happened, and everywhere - shock.
Witnesses told us that when the gunfire started some people took cover in the North Bondi Surf Life Saving Club. Once the threat was over, lifeguards helped the injured and used surfboards to carry them out.
Some people were clearly traumatised and provided graphic detail of witnessing the shooting and seeing people killed in front of them.
A photographer, Danny, was covering the Jewish holiday event.
Read more: What we know so far
He said he "locked eyes" with one of the gunmen, who then fired towards him. Danny said he was grazed by a bullet. He kept filming during the shooting, while taking cover.
Sam, from France, was working at Bondi. He went to the scene of the attack and saw almost a dozen people lying on the ground covered in blood. Sam described it as like a "war zone".
Rabbi Lei Wolff, from Central Synagogue in Sydney, went to Bondi as soon as he heard about the mass shooting. A dear friend of his, Rabbi Eli Schlanger, was killed in the attack.
Rabbi Wolff has called on people around the world to stand with Australia's Jewish community against terrorism.
(c) Sky News 2025: Photographer 'locked eyes' with gunman, as witness describes Bondi 'warzone'
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