NSW Rural Fire Service spokesperson Greg Allen said crews, including volunteers from across the ACT and NSW, were looking forward to a well-earned break.

The grassfire burning since Tuesday in the Tarago / Currandooley region was beginning to be brought under control after destroying more than 3300 hectares. It had since been downgraded to advice level.

"Crews have worked though the night to continue building and strengthening containment lines," Mr Allen said, with the plan for those lines to hold the fire so crews could contain it.

The fire at Mulligans Flat, which started late Wednesday afternoon eight kilometres north-west of Sutton, had been brought under control after burning more than 500 hectares in a matter of hours and had also been downgraded to advice level.

"The fire ran pretty hard yesterday with those hot and gusty conditions," Mr Allen said. "That fire is now contained."

He urged residents across the region to remain vigilant, follow the directions of firefighters and to contact local police if they had left their homes.

A crew changeover this morning saw fresh crews working across the region, with milder conditions forecast through the week expected to help firefighters finish efforts to contain the fires.

In the Tarago area, police said Braidwood Road and Goulburn Road between Lumley Road and the Kings Highway remained closed as they continue to monitor the Tarago fire.

On Wednesday, Sutton local Courtney Chalman was left wondering on the fate of his home and his bulldog, Zeus, when police wouldn't allow him past a roadblock on the way to his home.

"The worst thing is sitting and waiting, because the police didn't tell me much," Mr Chalman said.

Fortunately, a quick thinking neighbour got to his home to retrieve Zeus.

All roads previously closed due to the the Sutton fire had now reopened.

Picking up the pieces in the Tarago region on Wednesday was former Canberra surf-shop owner Fred Kuhn, who lost 43 of the 150 sheep he owned and stood in the burned paddock local vets had piled the dead in.

"I'm in denial," Mr Kuhn said. "It is very sad, isn't it?"

Exhibition Park in Canberra and Goulbourn Showground had opened their doors to take in horses who had to be relocated due to the fires.

On Wednesday evening, Canberrans could see water-bombing helicopters flying to the Sutton fire, with the smoke visible from over the hills on the Monaro Highway.

There had been earlier concerns of a fire in Gungahlin which the ACT emergency services said were untrue. They advised that Canberrans would receive alerts and warnings immediately in any such event.

With James Hall, Georgina Connery