A fisherman swept off rocks into the water at Piha is now onshore and being assessed by a paramedic.

Emergency services, including police, St John Ambulance, Westpac Auckland Rescue Helicopter and a surf lifesavers in an IRB, rushed to help after they were alerted at 9.52am that a man had been washed off rocks at the popular West Auckland beach.

A police spokeswoman confirmed just after 10.30am that the man was on the beach and being assessed by the rescue helicopter's paramedic. She did not know how the man had been retrieved from the water, where he was last seen floating near Nun Rock.

The man was believed to be wearing a flotation device.