A woman is in a critical condition in hospital after she was swept off rocks while fishing near Newcastle overnight.

The woman was with a friend fishing on a rock platform at Frazer Park, Lake Munmorah, about 7.35pm (Saturday 24 January 2015), when she was washed into the water.

Her friend grabbed a floatation device and jumped in after her but he was unable to bring her back to safety.

Emergency services were called to the scene, while a police officer attached to the Tuggerah Lakes Drug and Anti-Theft Unit patrolling nearby, entered the water to assist the pair.

He kept the woman afloat until she was winched out by the Westpac Rescue Helicopter.

Newcastle Water Police and Maritime officers then assisted the officer and the man from the water and returned them to shore.

The woman was taken to John Hunter Hospital where she is reported to be in a critical condition.

Inquiries are continuing.