Graphic emergency-room images of a Sydney Harbour shark attack victim have been shared online, sparking an urgent investigation.

Lauren O’Neill was badly wounded when a shark bit her on the leg while she was swimming near a jetty at Elizabeth Bay, in Sydney’s eastern suburbs, on Monday evening.

Neighbours helped pull the 29-year-old to safety and stemmed the bleeding before she underwent major surgery in St Vincent’s Hospital.

Images emerged on Thursday of O’Neill’s bloodied leg while she was in the emergency department.

“St Vincent’s takes patient privacy obligations extremely seriously and is investigating this issue as a matter of priority,” a spokesman for the hospital said.

“We have engaged with the patient and we have sincerely apologised for any part St Vincent’s played in the photos being taken.”

Health staff regularly take images of patients’ conditions for clinical care, staff education and forensic purposes.

But the taking of such images requires the prior consent of a patient, except when essential for clinical care, and staff are required to maintain the security of sensitive information.

A shark attack has prompted debate about the need for more anti-shark measures. Photo / 123rf

O’Neill on Wednesday asked for privacy after thanking medical staff and all who had come to her aid.

“(Lauren) wishes to thank her heroic and very kind neighbours for the critical assistance they provided her,” a statement issued on her behalf said.

“She would also like to thank the public for their outpouring of support and kindness and, as she turns to focusing on her recovery, asks that her privacy and that of her family be respected.”

The avid kayaker and swimmer remains in recovery at St Vincent’s Hospital, where she was rushed for surgery following the attack.

The incident was the first serious attack inside the harbour since 2009, when navy diver Paul de Gelder lost his right leg and hand to a bull shark.

It has prompted debate about the need for more anti-shark measures, including extra netted harbour pools, in order to protect swimmers.

But more shark nets in and around Sydney Harbour will not end shark attacks, NSW Premier Chris Minns has said.