Family in 'profound shock' after experienced firefighter killed in the line of duty

The heartbroken family of a national parks firefighter who was killed in the line of duty said they are in a "profound shock" as they paid tribute to him.

John Lohan died after he was crushed by a tree and suffered a heart attack while fighting a bushfire in Bulahdelah on the NSW Mid North Coast on Sunday night.

The 59-year-old was an experienced firefighter whose loss is being felt deeply within emergency services, the local community and his loved ones.

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His family said it was a "heartbreaking time" for them.

"The news of John's passing has come as a profound shock to us all," they said in a statement.

"John was a great father, loving brother, and wonderful friend to everyone who knew him. He will be greatly missed."

Lohan was a long-time firefighter for the NSW National Parks and Wildlife Service and had been based in Lake Munmorah for almost 30 years.

His colleagues said he was a "treasured" member of their team.

"He was an experienced firefighter who was deployed to fires across the state and was working as a divisional commander," NSW Parks and Wildlife Service said.

"John lost his life while undertaking a critical leadership role on the fireground, ensuring the safety of his firefighters and the community."

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Prime Minister Anthony Albanese and NSW Premier Chris Minns have offered their condolences to his family.

The bushfire has burnt more than 4600 hectares in the Myall Lakes National Park on both sides of the Pacific Highway between Crawford River and Nerong near Bulahdelah.

It has destroyed four properties.

Firefighters were conducting a backburn to protect properties on the northern and eastern side of Nerong on Sunday night.

Lohan was checking on his colleagues when the tree fell on him, Rural Fire Service Commissioner Trent Curtain said.

Police have set up a crime scene and are preparing a report for the coroner.

WorkSafe is investigating.

There are around 1000 NSW National Parks firefighters working alongside the Rural Fire Service and Fire and Rescue.

Crews are currently fighting dozens of fires across the state in sweltering conditions as temperatures exceed 30 degrees.

A bushfire in Bogee near Lithgow was escalated to an emergency warning this afternoon.

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