Firefighters were called to a commercial building after a discarded cigarette started a fire.
Crews descended on City Road, Fenton, after smoke was seen coming from the premises.
But it took them a while to locate the fire which was initially thought to be caused by a power failure.
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After ripping out floorboards and searching the nearby building, firefighters discovered a cigarette had fallen into a cavity and started the fire.
No one was injured in the incident, which happened around 2.30pm on Tuesday March 1.
A Staffordshire Fire and Rescue Service spokesman said: “Firefighters were called to business premises in Stoke-on-Trent on Tuesday following reports of an electrical fire.
“Hanley and Longton crew attended an address on City Road, Fenton at 2.30pm and found smoke billowing from the ceiling of the property.
“Firefighters isolated the electricity and removed the floorboards from the first floor in order to locate the source of the smoke.
“Crews located and extinguished a fire at 3:35 p.m. Other firefighters worked to extract smoke from the neighboring property.
“No one was hurt.
“The cause was later determined to be accidental, following a dangerously discarded cigarette that fell into a cavity and started a fire.
“A thermal analysis of both properties was carried out before firefighters left the scene at 4:20 p.m..”
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