Wrexham Council's Guildhall was evacuated as smoke was seen billowing from the building.
North Wales Fire and Rescue Service confirmed that two appliances were sent to Llwyn Isaf in the town centre.
Leader reporter Gwyn Griffiths, who was inside the building to cover a meeting, was one of those evacuated with staff and members of the public.
Smoke was seen coming from the top of Wrexham's Guildhall, above, as firefighters tackle the situation, below. Pictures: Gwyn Griffiths
They were allowed safely back into the building around an hour later.
A member of the fire service at the scene said they were unable to locate any fire, and the cause of the call-out was likely to have been steam from a boiler.
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