Australian military aircraft and vessels will be deployed to help emergency services in the fire-ravaged states of New South Wales (NSW) and Victoria.

Thousands of people fled to beaches in the south-eastern states on Tuesday as emergency-level fires spread.

In Mallacoota, Victoria, about 4,000 people sought shelter on the coast.

Two more people have been confirmed dead in NSW, bringing the fire-linked death toll to 12. Authorities say four people are missing in Victoria and another in NSW.

"We've got literally hundreds, thousands of people up and down the coast, taking refuge on the beaches," said Shane Fitzsimmons, commissioner of the NSW Rural Fire Service.

Fitzsimmons said it was "the worst fire season we have experienced here in NSW".

Bush fire season is nothing new to Australians, but this summer has been calamitous — and it’s far from over.

This fire season has been one of the worst in Australia’s history, with at least 15 people killed, hundreds of homes destroyed and millions of acres burned. And summer is far from over.

This week, thousands of residents and vacationers in southeastern Australia were forced to evacuate to shorelines as bush fires encircled communities and razed scores of buildings. Military ships and aircraft were deployed on Wednesday to deliver water, food and fuel to towns cut off by the fires.

Record-breaking temperatures, extended drought and strong winds have converged to create disastrous fire conditions.

As a severe heat wave gripped most of the country in mid-December, Australia recorded its hottest day on record, with average highs of 107.4 degrees Fahrenheit, or 41.9 degrees Celsius. The heat wave is continuing this week in southeastern Australia, with temperatures expected to reach 105 in Canberra, the capital.

The extreme heat has followed the driest spring on record. Most of New South Wales and Queensland have been experiencing shortfalls in rain since early 2017. The drought has hit the country’s most productive agricultural areas, including some of those now ablaze.

Credit: International News Agency