The Scottish Fire and Rescue Service said they could not confirm details about any controlled explosion, only that the service had received a call about a building at Longannet on fire at 2.47pm and crews were subsequently dispatched.
Scottish Power however insisted there had been a controlled explosion at the site this afternoon.
A Scottish Fire and Rescue Service spokeswoman said: “There are now seven crews in attendance tackling the fire as well as a height appliance and a control unit.”
She added that a media statement was expected to follow later this evening about the incident.
A statement from Scottish Power said: A spokesperson for ScottishPower said: “A further structure at Longannet, Scotland’s last coal-fired power station, has been brought down in a successful controlled explosion.
“Charges were used to blow down the site’s disused east bunker bay, previously used to store coal, with expected residual burning from some remaining coal dust resulting in some dark smoke being visible in the local area. The fire brigade attended to assist the demolition contractor as per their normal procedures.”
Longannet was closed in 2016, marking the commitment by both ScottishPower and parent company Iberdrola to decarbonise the economy. With demolition work still ongoing, over 28,000 tonnes of material removed from site so far, with 98.5 per cent of this being recovered/recycled.