Australia bushfires: 'Largest relocation ever' from New South Wales region expecting 'extreme' blazes

There are "monstrous" lines of Australians stocking up on emergency supplies and evacuating New South Wales' South Coast as authorities predict "extreme" fires to hit the region.

Earlier on Thursday, the NSW Rural Fire Service warned tourists to leave the region and put in place a "widespread extreme fire danger". By Saturday, it's believed conditions could become even more dangerous than the colossal fires that hit on New Year's Eve.

Andrew Constance, MP for Bega, says the evacuation is the "largest relocation out of the region ever". 

More than 380 homes have been destroyed there since Wednesday and supplies in the Australian region are running low as residents stock up and holiday-goers flee. Roads have become jammed with motorists wanting to escape the area which is being smothered by smoke. 

A spokesperson for supermarket chain Woolworths told The Guardian that it was working hard to keep stores stocked. 

"We understand it's an anxious time and thank customers for their patience as we manage the increased demand and the road closures," the spokesperson said.

Fuel is also running low at some petrol stations, but Constance says two tankers are being escorted into the region.

"Everyone needs to be patient. It might be an hour or so before it starts to clear," he told ABC.

"Fuel is coming into the region, which is great. We saw two tankers under escort last night and the police and the RFS, I want to thank them for escorting the vehicles in."

One of the towns most at risk of the devastating blazes is Bateman's Bay. Sydney Morning Herald reporters in the area say lines outside service stations are "monstrous". 

"Just a section of the very long line of cars trying to get out of Batemans Bay before Saturday. Barely moving at a crawl," tweeted one person, with a photo showing two lanes of gridlock traffic leaving the town.

"Gridlock all the way through Ulladulla, similar scenes in Milton, Nowra and Batemans Bay. Just met a woman who's arrived in Ulladulla after leaving Depot Beach - 30km south - at 7am," said another.

Further inland from the coast, the Kosciuszko National Park has been closed due to the large fires, which could soon expand. Those in the park or staying at its resorts have been told they must evacuate by Friday night as an "essential measure to protect life".

There are more than 110 fires in New South Wales, while about 50 burn in the southern state of Victoria. Up to 18 people are believed to have been killed since the fires started.