Emergency crews are working to protect the Australian town of Tennant Creek with containment lines as a huge wildfire threatened the remote Outback community of 3,000.

The fire has scorched 3,900 square miles of grass and scrubland in the Northern Territory east of Tennant Creek, a former gold mining town.

Police acting commander James Gray-Spence said authorities had worked through the night to burn protective containment lines east and south of the town.

“There is a high level of confidence that those containment lines are in place, planned and prepared,” Mr Gray-Spence said.

Wildfires are common across Australia’s northern tropical region during the current dry season that will end when the monsoons arrive during the Southern Hemisphere summer.

Because water is in short supply across the region, fire fighting largely involves excavating fire breaks with earth-moving equipment.

But teams were also using water bombers and strategic backburning against the fire near Tennant Creek which began last week.

Charles Darwin University wildfire researcher Rohan Fisher said the fire was unusual in its large size and that it was encroaching on a community. Fires rarely threaten communities in Australia’s sparsely populated north.

“It is one of the largest events that we’ve seen for a while,” Mr Fisher said.

“Fires of around this scale are not that uncommon in really remote parts of Australia, although they’re usually not reported on.”

Unusually abundant rain in recent years meant there was more fuel in the landscape than usual, he said.

The Northern Territory government has declared an emergency situation in Tennant Creek and the surrounding Barkly region, which gives police emergency powers to move people and assets.

Police commissioner Michael Murphy said he was confident the town would not need to be evacuated and the emergency declaration was a precautionary measure for public safety.