A second person has been confirmed dead in fires raging across eastern Victoria, most of which has now been declared in a state of disaster ahead of an "unprecedented" fire threat over coming days.

Devastating scene from Mallacoota and conditions are set to worse at the weekend. Credit:Rachel Mounsey

Premier Daniel Andrews declared the emergency for six local government areas in Victoria and Alpine resorts, the first time such powers have been used by the state government since being recommended after the Black Saturday bushfires.

The areas affected are: East Gippsland Shire, Mansfield Shire, Wellington Shire, Wangaratta Rural Shire, Towong Shire, Alpine Shire, Mt Buller, Mount Hotham and Mount Stirling Alpine Resorts.

Police said it was believed the second Victorian man to die suffered a medical episode while fighting the fires.