Dirty black smoke wafted over Derry shortly before 9am on Monday morning, September 5, after a large pile of rubbish was torched at a building site in Top of the Hill.
Firefighters who were tasked to the blaze believe it was started deliberately.
A Northern Ireland Fire and Rescue Service spokesperson said: “Northern Ireland Fire and Rescue Service (NIFRS) received a call at 8.56am to a report of a fire at the Strabane Old Road, Gobnascale area of the city this morning (Monday, September 5).
“One Fire Appliance from Crescent Link Fire Station was deployed to the scene of a large quantity of rubbish well alight at a building site in the area. Firefighters using a hosereel jet dealt with the incident.
“Northern Ireland Fire & Rescue Service finished at the scene at 10:03am and the fire is being treated as deliberate.”