The injured were transported to the hospital, with one person in serious condition and the others sustaining minor injuries, according to Civil Protection.
The fire at the building on Rua Correia de Sá 245 has been extinguished, and the situation is under control.
The alert was issued to Civil Protection at 21:43 on Thursday.
According to the website of the National Authority for Emergency and Civil Protection, at 23:22, 29 operatives supported by 10 vehicles remained at the scene.
