A fire, set in the open near some derelict buildings in Eastfield, is believed to have been started deliberately.
Three teenage boys wearing hoodies were reported to have run away from the scene and police officers conducted a search of the area, but no one was located on this occasion.
North Yorkshire Police officers attended the incident with North Yorkshire Fire and Rescue Service on April 30 at 7.50pm.
On arrival firefighters confirmed a large amount of rubbish had been set alight inside a derelict outbuilding and the fire was extinguished using a hose reel.
A spokesperson for North Yorkshire Police said: "Needless to say, setting fires in this way is extremely dangerous, and this foolish activity could have had serious consequences.
"If you have any information about who is responsible, contact us on 101, quoting reference number 12190078078."