Firefighters were called to Tulloch Court in Hilltown, Dundee, when the blaze broke out in a sixth-floor flat in the early hours.
A number of homes were damaged by water and residents were given alternative accommodation at a community centre. No-one was injured.
A spokesman for Dundee City Council said most residents would be able to return to their homes after safety checks by electricians and building control.
Tayside Police said the fire was being treated as suspicious and a joint investigation was taking place with Tayside Fire and Rescue Service.
Police are appealing for witnesses to the fire and have urged anyone with information to contact them.