STAMFORD - Stamford police are investigating an early morning fire at an illegal basement apartment.

Firefighters were called to 42 Halloween Blvd., where they found a pregnant woman and her 7-year-old daughter. Both were taken to the hospital and treated for smoke inhalation, but are expected to recover.

Police say the fire started in the furnace room and was likely sparked by a gas can. They are trying to determine whether a spark from the furnace was to blame, or if it was arson.

Police say three people were living in the basement apartment, which is located off of the furnace room and is an illegal subdivision.