Ten people are hospitalized after a fire in a West Humboldt Park apartment building.

The Chicago Fire Department said the fire started in the basement of a two-story residence on Karlov Avenue around midnight. First responders flooded the scene, and video showed a chaotic scene, with multiple people being put into ambulances and firefighters stretching hose lines down the block.

Residents were forced to evacuate into the bitter cold. Fire officials said 10 people were taken to hospitals, including an 81-year-old woman who suffered smoke inhalation.

Flor Giles, who lives at the property, said the elderly woman is the landlord for the apartment building and a small home in the back of the property. With her daughter translating, Giles said she is worried for the landlord, who she considers a close friend.

Giles has lived at in her home for the last 25 years. Parts of the siding were melted by the flames in the apartment building.  She said she was devastated to come home from work and find her neighbors, including children, displaced from their homes.

A source with the Chicago Fire Department told CBS News Chicago that at one point people were throwing children out of the building's lower windows to get them to safety.

Giles said her gas is turned off because of the fire. The apartment building was badly damaged, and all windows are now boarded up. What's next for her and many others is not clear.

CFD said the cause of the fire remains under investigation.