A fire which threatened homes near Gracetown is under control.

Picture by Becky Felstead, Busselton Dunsborough Times

People near Gracetown were told to prepare to leave their homes as a bushfire burnt fast and out of control in the South West region.

The Department of Environment and Conservation issued a watch and act alert for people in the area from Gracetown to Juniper Road, the Gracetown townsite and West of Caves Road. The alert has now been downgraded to an advice warning.

The fire is now under control and firefighters will monitor the scene overnight.

The fire started near the North Point carpark on Cowaramup Bay Road and was moving fast in a north-westerly direction

Firefighters, a helicopter and two fixed-wing water bombers fought the blaze.

Approximately 50 hectares has been burnt. The cause of the fire is unknown.