Firefighters were called to put out a fire in a communal bin unit.
A crew from Southsea went to Frobisher House in Hawke Street, Portsea, at 6.10pm on Friday.
One hose reel was used by firefighters to put out the blaze.
It is not known whether the fire was an accident or started deliberately but it was put out quickly. Anyone with information should contact police on 101 or Crimestoppers anonymously on 0800 555 111.