Residents were evacuated and seven fire engines called to a Portsmouth flats complex - because of a smouldering cigarette left in an ashtray.
Smoke set off an alarm at Admiralty Quarter, in Queen Street, Portsea, at about 8.15pm last night.
Firefighters were called by the supervisor of Queen Anne House, one of the buildings adjacent to high-rise Admiralty Tower, after a smoke alarm went off on the fourth floor.
When firefighters arrived, many residents had evacuated the building.
Alex Hay, crew manager at Southsea fire station, said: ‘Someone had an ashtray made of paper composition.
‘They had left the cigarette in the ashtray and gone out for something.
‘They thought the cigarette was out, but it just burned through the ash tray and singed the material that it was sitting on.
‘It could have been a lot worse than it was.’
The fire was out by the time firefighters arrived, but there was a lot of smoke to clear.
Mr Hay said: ‘The reason there were that many appliances was because it’s a high-rise block.
‘It was a predetermined response.’
He added: ‘The safety message is whenever you smoke in the house make sure the smoking material is fully extinguished before you leave it.’