A woman has suffered significant injuries to her leg in a suspected shark attack at a private wharf on Sydney Harbour.
NSW Ambulance said multiple crews, including the helicopter, were sent to Billyard Avenue in Elizabeth Bay about 7.45pm.
The woman, aged in her late 20s or early 30s, suffered significant blood loss.
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A nearby veterinarian applied a tourniquet to stem the bleeding before the woman was rushed to St Vincent's Hospital in a critical condition.
The woman's injuries are believed to be severe and to her lower right leg.
A woman who witnessed the incident said her wife was the vet who potentially saved the victim's life.
"My wife's a vet and she basically bandaged it up … it's pretty hectic actually, but she seems to be OK, she's been in a lot of shock and so am I," the woman told 9News.
"We got some bandages, we kept her warm, and my wife basically bandaged her up to stop the bleeding."
She added that had the woman been further out in the water, "she wouldn't have survived".
NSW Police said officers at the scene were told the woman had been swimming off the wharf at the time.
"Marine Area Command are patrolling the area as a precaution," they said.
Whilst all indications are that the woman suffered a shark bite, Primary Industries will investigate to confirm.
MORE TO COME