Fire investigators are trying to determine what caused the explosion and apartment collapse that lead to the rescue of two women and a dog from an apartment building on Chicago's South Side.
It happened in the 5800 block of South Calumet Avenue in the Washington Park neighborhood on Sunday night.
When Chicago Fire Department crews arrived, the building had already fully collapsed, and people were trapped below piles of rubble.
Neighbors describe the explosion as a loud boom. It rocked the neighborhood, moving furniture in several people's apartments.
"The furniture was moving from one side of the floor to the other side but it was dark. So I tripped over the furniture so I could get out of there," said Ernest Thomas.
One of the women is 51-years-old, the other is 78-years-old. The 51 year-year-old woman has been released from the hospital. The 78-year-old was in serious to critical condition when she was pulled from the rubble. Investigators say she was talking. They were the only two people who lived in the building.
The rescued dog was identified as a pit bull named Tigger.