A woman in her 30s was left in critical condition on Saturday after a large shark bit her at Coogee Beach, turning a clear morning swim into a rescue scene within minutes. She suffered injuries to her arm and leg and was taken by road to St Vincent’s hospital after being treated on the sand.

The attack happened just after 11am, when multiple New South Wales Ambulance crews joined members of the public and police already trying to keep her alive. Surf Life Saving NSW said she was taken to hospital semi-conscious and breathing, after bystanders pulled her from the water and began first aid before emergency services arrived.

That is the detail that makes the attack so hard to process: one regular swimmer said the water was perfect, clear and still, yet a shark was already close enough for a scream to go up and the alarm to sound. The swimmer said the attack happened about 30 metres from their group, blood was visible in the water, and the shark was seen swimming in yellow-green water not quite in the shallows but not far out either.

Police rendered first aid before paramedics took over, then cleared nearby Coogee Oval so a Careflight helicopter could potentially airlift the woman to hospital. Instead, she went by road to St Vincent’s, while beaches in Sydney’s east were closed as the morning unfolded. The exact type of shark was not immediately answered, but the emergency response left little doubt about the seriousness of the bite and how quickly a crowded beach can become a trauma scene.