A hazard reduction burn around North Head on Sydney's Northern Beaches which jumped containment lines has prompted the evacuation of nearby residents.
NSW Police said in a statement on Saturday that commercial premises and residential properties around North Head had been evacuated.
Those still in their homes are advised to remain inside with their windows shut until told otherwise, while others have been told to avoid the area.
The hazard reduction burn jumped containment lines about 2pm on Saturday.
The NSW RFS said the fire was under control and no homes were under threat, but upgraded the blaze to "watch and act" level just after 4pm.
It is burning to the southwest, fuelled by northeasterly winds.
The RFS in a statement said it was on the scene at the 10-hectare blaze, as well as Fire and Rescue NSW crews and the National Parks and Wildlife Service.