The CFA issued an emergency warning for the area about 10pm and said the blaze, which was creating spot fires one to two kilometres ahead, could hit between midnight and 4am.

Firefighters were yesterday being flown to a remote location on the Diamantina River near Mount Hotham in a bid to stop the Harrietville North fire from spreading into forests with heavy fuel loads.

Firefighters now say without significant rain, the battle in and around Mount Hotham and Falls Creek will continue for another week at least.

Yesterday helicopters ferried the crews to the firefront from the Harrietville cricket oval at 10-minute intervals, while a giant Skycrane dumped its 9000-litre loads on inaccessible terrain.

The firefighters in sets of six lugged 15-kilogram backpacks, rake hoes and chainsaws onto the helicopters.

Deputy incident controller at Ovens Peter Creak said the aim was to keep the fire inside the containment lines.

“We are trying to hold the fire in what is steep and difficult terrain in the Diamantina area,” he said.

“The firefighters are being taken to a helipad and attempting to keep the fire behind the Diamantina River.

“We see this as a critical point in the fire fight — there is unburnt fuel to the east and south of the river.”

“If the fire gets past there is a long-term threat to Falls Creek and more immediate threat to Mount Hotham.”