London Fire Department crews were called to the scene of a fire on Oxford Street East, across from Fanshawe College, on Monday.
Two people were taken to hospital with serious injuries after a fire broke out in the apartment building around 11 a.m.
One person was taken from a third floor apartment using a ladder while the second person was found by firefighters inside a second floor apartment and brought outside to waiting EMS.
Officials say a second floor apartment was gutted by the flames and a window blown out. The entire second floor suffered extensive heat and smoke damage, and there is smoke damage throughout the building.
About two dozen displaced residents were being cared for on an LTC bus and overnight accomodation was being arranged.
The building is occupied mainly by low-income tenants.
Damage is estimated at $150,000 and an investigation into the cause of the fire continues.