The main street of the Bega Valley town of Cobargo has been devastated by an out-of-control bushfire which has left a father and son dead.

Key points: Cobargo was engulfed by an emergency-level bushfire

Cobargo was engulfed by an emergency-level bushfire Residents described how the drought left them with no water to defend their property

Residents described how the drought left them with no water to defend their property RFS Commissioner Shane Fitzsimmons said dozens of buildings had been destroyed and two people were feared dead in the town

Father and son Robert Salway, 63, and Patrick Salway, 29, perished in the blaze, which tore through the Bega Valley town of Cobargo early Tuesday morning.

The pair had stayed behind to defend their property in Wandella, 10 kilometres west of Cobargo, after Robert's wife — who is also Patrick's mother — evacuated.

She returned on Tuesday morning and discovered their bodies.

Part of the main street of Cobargo has been flattened by the bushfire. ( Supplied. )

RFS Commissioner Shane Fitzsimmons said he expected the "significant impact" of the blaze had damaged or destroyed "dozens" of buildings in the historic village.

Debbie Wilson and Phillip Bragg were on holidays in Cobargo and witnessed the chaos unfolding from their caravan parked behind a local pub.

"I was up at about 3:00am due to all the commotion of people coming and going there," Ms Wilson said.

The couple tried to evacuate from the area around 5:00am, but were turned around as they drove to Bermagui.

"I was just watching everything burn," she said.

"All I can see now is a lot of smoke and fire trucks — just a big whoosh of black smoke go up."

'You could hear it roaring like the ocean'

Brenda Whiffen watched as the out-of-control blaze consumed her neighbour's shed. ( Supplied: Brenda Whiffen )

Long-term residents Brenda Whiffen and her husband spent the night working to protect their property after embers brought the fire through about 1:00am.

"We came outside and you could see the red glow, but you could hear it roaring, that was the scary bit. You could hear it roaring like the ocean," she said.

"And it just came so quick, because of the embers. One would start up here and another one would start somewhere else."

Together the pair saved two homes on the property, about three kilometres from Cobargo's town centre, but their farmland and other buildings were destroyed.

"I just went round and round watering it, that's all I knew how to do," she said.

"We lost the hay shed. Don't know what we're going to feed the animals with now."

What the main street of Cobargo, population 776, looked like before the bushfire. ( Supplied: Google Maps )

The main street was engulfed by flames, with dozens more buildings destroyed or damaged. ( Supplied )

By late morning, she said they believed the worst was over.

"It's cool now, we've got the southerly change so that might help," she said.

Ms Whiffen said she was deeply saddened by the damage to the town, particularly the ravaged main street.

"This is our old home town — I've lived here since I was six, my husband's lived here all his life, my kids were reared here," she said.

'This is what hell looks like'

Cobargo Hotel owner David Allen said he took matters into his own hands upon seeing how overwhelmed local firefighters were.

"I came back into town and that's when embers started spot fires everywhere," he said.

"We got the fire hoses out, the fire brigade guys were flat out and we thought, we'll just try and save the pub."

Mr Allen broke down as he described the ferocity of the blaze.

"As someone said, this is what hell looks like, and we saw it last night," he said.

"It's just so fast, and that's what caught people unawares."

Space to play or pause, M to mute, left and right arrows to seek, up and down arrows for volume. Watch Duration: 1 minute 10 seconds 1 m 10 s Cobargo in flames after bushfire tears through town ( Supplied: David Allen )

Mr Allen said that by lunch time, a number of locals and their animals were taking a rest at Cobargo Hotel.

"We've had a few people with some burns come through... I think they've been taken to the evacuation centre," he said.

But he couldn't be sure what the extent of the impact had been on people in the fire's path.

"To come out of it with no lives lost would be a miracle I think."

'We've got no water left so we weren't able to defend'

Susanne Lewington, who owns the Breakfast Creek Vineyard in Bermagui, near Cobargo, was forced to evacuate her property at 5:00am.

She was speaking at a shelter down the road and did not know if the devastation has reached her property.

"It's very eerie down here, it's really smoky, there's ash everywhere," she said.

"I have no idea if we've lost our property. If we have a wind change it could go because we've very close to the creek and we're close to the forest.

"The sky was black, we only got daylight a few hours ago."

She said the drought had left her property without any significant water bodies that may have helped dampen the blaze.

"There's not much left on the property, about 100 ducks, four cattle and 10 sheep, that's all we've got left because I had to sell the rest due to the drought," she said.

"We've got not water left so we weren't able to defend."