Washington Park building collapse caused by natural gas buildup, officials say

CHICAGO (WLS) -- Officials say a natural gas buildup was the cause of a building collapse that left two people hospitalized in the city's Washington Park neighborhood.

A natural gas buildup from an appliance or customer-owned pipe caused the building to come crashing down around 7 p.m. Sunday near 58th Street and Calumet Avenue, officials said.

Two women, ages 51 and 78, were rescued from the debris, along with a dog. The 51-year-old was hospitalized in serious condition and the 78-year-old was hospitalized in critical condition, officials said.

There were four separate apartments in the building, which was built three years ago. The two women were believed to be the only ones inside at the time of the collapse.

PHOTOS: Apartment building collapses in Washington Park