Police say they are treating a fire in the former Forfar swimming pool as deliberate.
Firefighters were called to The Vennel just after 6.30pm on Tuesday.
Locals said there was smoke coming from the roof of the 114-year-old building.
The building, which was sold by Angus Council last year, has been lying empty since 2017.
One resident told The Courier she only became aware of the smoke when the firefighters arrived in the street.
Smoke seen coming from roof of former Forfar swimming pool
She said: “I saw the first appliance arrive a couple of hours ago.
“One of the firefighters pointed up to the roof and I saw the smoke coming out.
“I never saw any flames as another engine arrived.
“They were taking hoses around the back and they also entered via an old fire exit and smoke began coming out of there as well.
“The water was pouring out of that door as they tackled the fire.”
A spokeswoman for the Scottish Fire and Rescue Service said: “We received a report of smoke coming from a disused building.
“Crews from Forfar and Kirriemuir were mobilised to the scene.
“One hose reel jet was in use and four breathing apparatus.
“Power rescue equipment has also been used at the scene.
“We received the stop message at 7.45pm.”
Police treating Forfar fire as ‘wilful’
Concerns were raised in February that the pool had become a magnet for local youths.
A spokesperson for Police Scotland said: “Around 6.55pm on Tuesday, officers received a report of a fire at a premises at The Vennel, Forfar.
“The fire is being treated as wilful and inquiries are ongoing.”
