A search and rescue operation is underway tonight for two kayakers believed to be missing in treacherous water off Sydney's northern beaches.
A witness reported seeing two kayakers off Long Reef headland this afternoon who appeared to be in distress.
Stephen Leahy, chief executive of the Westpac Life Saver Helicopter Rescue Service, said the witness then saw one of the kayakers come out of their kayak and swim towards the other, with both kayakers then swept further out to sea.
The witness phoned the police, triggering the rescue operation.
Sydney was hit with gale force winds today and Mr Leahy said the water was "very, very choppy" and that there was a lot of sea mist.
The Westpac helicopter was tonight sweeping the northern beaches from Manly to Avalon, up to 8 kilometers out to sea.
The crew are using a thermo-imaging camera to try to locate the kayakers.
No reports have been received of missing persons so far.