A woman has died and a man is fighting for life after being attacked by a shark on the NSW mid north coast.

Emergency services rushed to Crowdy Bay, south of Port Macquarie, around 6.30am on Thursday following reports two people had been bitten by a shark.

Despite desperate efforts by witnesses and paramedics, the woman aged in her 20s died at the scene.

A man, also aged in his 20s, has been airlifted to hospital in a critical condition with serious injuries.

The beach has been closed and officers will liaise with experts from the Department of Primary Industries to determine the species of shark involved.

A report will be prepared for the Coroner.

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