Three people have been arrested after allegedly lighting fires in NSW as crews battled more than 80 blazes and catastrophic conditions across the state.
Rural Fire Service Commissioner Shane Fitzsimmons slammed the alleged fire bugs - males aged 13, 32 and 40 - for the "heinous crimes".
"How dare they," he told reporters in Sydney in Sunday.
"You put the lives of our firefighters at risk. How dare anybody add to the extraordinary conditions we're experiencing."
A 32-year-old man was arrested on Sunday afternoon after two fires were deliberately lit at Nabiac on the NSW north coast.
The man is being questioned by detectives.
Earlier, a 40-year-old man was arrested on the Central Coast after fire crews were called to a blaze in Mango Creek.
Police said the fire was extinguished and nobody was injured.
The man taken to Gosford police station and charged with setting fire to land during a total fire ban, intentionally causing a fire and being reckless as to its spread. He was due to appear in the Wyong Bail Court.
"Police and emergency services continue to remind people to report any suspicious activity about people they believe may be involved in deliberately lighting bushfires," police said in a statement.
Police have also charged a teenage boy with arson offences in NSW's central west.
A witness told officers they saw the 13-year-old, who was part of a group of teenagers, light a grass patch in an industrial area of Orange on Saturday evening.
The group fled, but the boy was later taken to the Orange police station and charged with destroying property, setting fire to the property of another and failing to comply with direction of the minister.
He was granted bail and is expected to appear in a children's court on Monday.
No structures were damaged but 100 wrecked motor vehicles were affected, police said.
The temperature in the region at the time was approaching 40C.
A total fire ban was in place for the entire state on the weekend with fire authorities describing the catastrophic conditions as "off the conventional scale".
