The fire was reported at about 1:20 a.m. Wednesday in Arvada. Three people were taken to the hospital but two of them later died, the Arvada Fire Protection District said. The condition of the third person in the hospital wasn’t known.

Multiple animals also died in the fire although fire district spokesperson Amber Jones told KUSA-TV that two dogs survived, one of which was taken to a veterinarian.

Firefighters are investigating how the fire started.