A search is underway for a private helicopter after it disappeared from flight radar near Newcastle last night.
Police say they haven't heard from the aircraft since it faded off the radar about 6.30pm yesterday.
The search is being co-ordinated by the Australian Maritime Safety Authority in the Anna Bay area in Port Stephens.
Water police and a rescue helicopter are assisting, with emergency workers still trying to confirm how many people were on board.
An Australian Maritime Safety Authority spokesperson said initial reports suggest there were four people on board but this has not been confirmed.
Westpac Rescue Helicopter Service said one of its helicopters was in the air at the time.
"Our aircraft is still up in the air in that area after the report of an aircraft crash," a spokesman said last night.
"There was a call through air traffic control at Williamtown that they'd lost contact with an aircraft."
A severe weather warning was in place last night for destructive winds with peak gusts in excess of 125km/h in the area.
Any one with information is asked to contact Triple Zero.
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