A teenage volunteer firefighter has been charged with deliberately lighting bushfires in western Sydney.

The 17-year-old was arrested early yesterday in the NSW lower Blue Mountains before being charged with multiple offences.

His arrest was part of an investigation by Strike Force Tronto, set up to apprehend bushfire arsonists.

Detectives identified a pattern of  deliberately-lit bushfires within the greater Wallacia area between Monday, June 23 and Sunday, September 7.

Investigators, with help from the NSW Rural Fire Service, identified a teenage boy who was allegedly responsible for lighting the fires and then responding to each one in his role as a volunteer firefighter.

He has been charged with three counts of intentionally starting a fire and two counts of false representation.

He was refused bail and appeared at a children’s court yesterday.

Anyone with information that may assist investigations into deliberately lit fires is urged to contact Crime Stoppers on 1800 333 000.