Nine people are dead after a fire raged through a Memphis, Tennessee house early on Monday (local time).
Five children and four adults died from the blaze. Most were killed by smoke inhalation, the others from burn injuries.
"This is the most tragic loss of life in a single fire incident since the 1920s," Memphis Fire Department Chief Gina Sweat said at a news conference.
She said firefighters were called out after an emergency call was made early in the morning.
However, they needed to break through "security doors" to get into the house, and the windows were covered with metal bars.
The home was filled with smoke when they gained entry, Ms Sweat said, and it wasn't clear if the occupants had been trapped inside the house by their own security systems.
One child remains in critical condition.
Ms Sweat said the cause of the fire was under investigation.