A Rural Fire Service volunteer accused of deliberately lighting several bushfires in the Hunter told investigators he sparked the blazes because he was bored, a court has heard.
Jack Hardridge, 18, was refused bail in Maitland Local Court on Thursday after being charged with 13 counts of intentionally causing fire and being reckless as to its spread, and two charges of destroying/damaging property.
Police allege Mr Hardridge deliberately lit fires in grassland at Weston, Pelaw Main, Bellbird, Greta, Aberglasslyn, Melville, and Cessnock in July and August this year.
They also allege he attended some of the blazes as a Rural Fire Service volunteer to help with the response.
Mr Hardridge applied for conditional release in court on Thursday.
The prosecution said there was an "overwhelming amount of evidence against the accused", including witnesses, CCTV footage and admissions.
The court heard that Mr Hardridge had told investigators he was "bored" when asked why he had lit fires - on some days allegedly as many as three.
One burnt 16,000 square metres while another scorched 11,000 square metres.
The court also heard others may have been involved in lighting the fires.
Mr Hardridge's solicitor Julia Clarke said her client had made admissions to police regarding most of the charges.
She said he would abide by 24-7 house arrest if granted bail, and that he would be "vulnerable" in custody.
"There is no getting away from the seriousness of the allegations," she said.
Magistrate Ron Maiden said the charges were "extremely serious" and that the risk of re-offending while out on bail could lead to "catastrophic" results.
"He's probably fortunate that greater harm and damage has not been done," he said when refusing the bail application.
Detectives from the State Crime Command's Arson Unit arrested Mr Hardridge at an Aberglasslyn home on Wednesday morning as part of an investigation by Strike Force Glenarvon.
Detective Acting Superintendent Richard Puffett told a Sydney press conference the 18-year-old was arrested after a "lengthy and tenacious" investigation.
He said the alleged behaviour was "of the highest scale and of a serious nature".
"We're still exploring the motives behind the offending that we allege took place over some weeks," he said.
"He is attached to a volunteer fire agency and he has been involved in the fighting of those fires following the ignition."
Acting Superintendent Puffett said one of the fires related to "a vehicle and a whole bunch of tyres", and flagged that crimes of this nature would be treated extremely seriously as summer approached.
"We're extremely concerned that the season that is approaching will be busier, will be hotter and more extreme than the previous two seasons," he said.
"We implore members of the public to call out any suspicious activity in bushland whether that be vehicles or persons that don't appear to be having a purpose or being in the wrong place at the wrong time. Please call us to investigate these occurrences."
Mr Hardridge will face Cessnock Local Court on September 13.