Sixty firefighters were involved in yesterday's Fermanagh blaze, the Fire Service says.
An investigation into the blaze, at commercial premises on the Tattygare Road in Lisbellaw, is ongoing.
However the Northern Ireland Fire and Rescue Service believe at this early stage that a malfunctioning generator may have been the cause of the fire.
The fire sent large clouds of smoke billowing into the sky yesterday after it started at around 2pm.
Group Commander Andy Burns said resources had to be called from Belfast, Omagh and Strabane to “help and support the operation”.
He added that at this “early stage” they believe an electrical generator “had malfunctioned” but that “the main cause of the fire will be investigated”.
The NIFRS initially sent eight fire appliances to the operation - one each from Enniskillen, Lisnaskea, Clogher, Armagh, Fintona , Irvinestown, Belleek and Omagh. An aerial appliance, water tanker and 'high volume pump' were among the resources deployed.
