Two volunteer firefighters have been killed in the battle to contain a fierce blaze that ripped through villages southwest of Sydney.

Tributes have been made for the Rural Fire Service volunteers killed last night when a fallen tree caused their tanker to roll as they fought fires south of Sydney.

Horsley Park Brigade deputy captain Geoffrey Keaton, 32, and firefighter Andrew O’Dwyer, 36, were both killed just before midnight in the crash.

Mr O’Dwyer’s posted on Instagram shortly before the crash, showing the truck convoy at Picton on his night shift.

RFS commissioner Shane Fitzsimmons said Mr Keaton’s family had a tradition of volunteering and his father had been out fighting the Gospers Mountain blaze when he lost his son.

Mr Fitzsimmons said they were “well-respected” and from a “close-knit brigade”.

“They work together, socialise together, they’re very interactive together. Their respective partners and wives shared a lot in common with their camaraderie and connection with the brigade,” he said.

“Geoff has a young son Harvey, and Andrew has a young daughter Charlotte, and both of those children were born two days apart back in May so they’re 19 months of age, which just terrible.”

The 2 firefighters killed in a vehicle accident last night are Deputy Captain Geoffrey Keaton 32yrs & Firefighter Andrew O’Dwyer 36yrs, both from Horsley Park Brigade. Our thoughts are with their family, friends & fellow brigade members. #nswrfs pic.twitter.com/p3Y8zX3hBj — NSW RFS (@NSWRFS) December 19, 2019

Mr Fitzsimmons said the families were in “extraordinary shock”.

In an emotional press conference this morning, Emergency Services Minister David Elliott described it as a “real tragedy”.

“This really is a black arm band day for the Rural Fire Service, indeed the entire firefighting fraternity,” Mr Elliott said.

“The loss of these two young men, just dads from western Sydney, is a real tragedy.

“The commissioner is ensuring that all of these firefighters and their families receive the welfare and support that they deserve and I know it’s what the community will demand.

“I appeal to all firefighters to carry on their duties in the memory of those lost overnight and I join the Premier in making sure the state provides every level of respect and support that the families require.

“I’m very confident that those firefighters’ families will find themselves wrapped around with love and that is only appropriate.”

NSW Premier Gladys Berejiklian also paid tribute to the two men, calling them “heroes”.

NSW has tragically lost two heroes. Our thoughts are with their loved ones and the extended RFS family as we come to terms with the devastating news. — Gladys Berejiklian (@GladysB) December 19, 2019

At the Horsley Park Rural Fire Brigade headquarters, in western Sydney, where both volunteered, family and friends gathered to commemorate and celebrate their lives.

Throughout the day members of the NSW Fire Brigade, community members and dignitaries, including NSW premier Gladys Berejiklian, trickled in to pay their respects.

A makeshift memorial outside captured the mood of the small and tight-knit community as wellwishers stopped to lay flowers and tributes. “Not all heroes wear capes, sending our prayers, thoughts and strength,” read one card.

“To our hero, thank you for your service. RIP,” said another.

Helmets emblazoned with “Keaton” and “O’Dwyer” were laid out alongside the bouquets of flowers as members of the 70-strong Horsley Park RFS brigade consoled each other.

One of Mr O’Dwyer’s colleagues at a local grocery store described him as: “Caring, out there, happy, just a good man.”

One of Mr Keaton’s friends described the feeling of reading headlines of two rural firefighters dying before seeing a familiar face in the pictures. “Geoff smiled readily and easily,” he said.

“His absence will be felt keenly by his friends, family, partner and son. His son will grow up knowing his father died a hero.”

Mr Keaton joined the NSW RFS in 2006, was the deputy captain of the Horsley Park brigade and is survived by his partner Jess and son Harvey, Mr O’Dwyer joined in 2003 and is survived by his partner Mel and daughter Charlotte.

A GoFundMe campaign for the two dads has already raised thousands.

The fund was launched by former firefighter Warren Spriggs, from Wollongong an hour south of Sydney.

He was devastated by the news of the accident and decided to launch the page to help the families impacted.

Tragic pictures from Horsley Park Rural Fire Brigade showed the heartbreaking memorial and tributes left by the two dads’ colleagues.