As many as 20 people were on a balcony of a three-family home on Campfield Avenue in Hartford when it collapsed on on Saturday night.
Officials say the family members were gathered on the rear, second-floor porch for a family celebration when the floor of the porch gave way and caused several people to fall to the first floor.
Fifteen people were taken to the hospital, Hartford Fire Chief Reginald Freeman said. One of those people was able to walk away from the hospital upon arriving to the emergency room. Authorities say none of the injuries were considered life-threatening.
The first of the patients transported to the hospital was an infant, according to a Hartford fire official. Witnesses report seeing young children transported to the hospital in ambulances.
Personnel from the Fire Marshal's Office and Hartford Licenses and Inspection responded to the scene. The residence was deemed habitable.
The cause of the structure failure remains under investigation.