FIREFIGHTERS have worked through the night to build control lines to contain a fire that's threatening small communities in North East Victoria. 

The Country Fire Authority says the Yea-Murrindindi fire is burning on the western and eastern side of the Black Range threatening Connellys Creek, Crystal Creek, Scrubby Creek and Native Dog Creek.

It's burned 100,000 hectares and is moving northeast.

In the Yarra Valley, fires continue to rage southeast of Toolangi and east and north of Healesville.

Residents are warned to remain vigilant in case of ember attack and changing conditions.

Communities in Healesville, Chum Creek, Badger Creek, Steels Creek, Dixons Creek, Yarra Glen, Toolangi and Castello are all advised to remain alert to fire activity.

CFA spokesman Darren Grevis-James says southerly winds are expected to pick up and push the fire in a northerly direction and there are a lot of town and hamlets in its path.

AAP