Gatineau firefighters were investigating after a fire tore through a residential building around 4 a.m. Sunday.
The fire service reported only one injury for a tenant who had smashed through a window to escape.
People were treated for smoke inhalation, but nobody was seriously hurt.
Firefighters estimated the damage for the blaze at 156 rue Archambault at $370,000 and were still trying to figure out how the fire started.
The fire department said as many as 30 people had been displaced from their residences because of the fire.
Link to original article in Ottawa Citizen.com: Gatineau fire displaces up to 30 residents