Early Monday morning, firefighters were called to a first-floor apartment in a five-story mid-rise building on McCue Road near Westheimer Road.

Because it was a large building, the Houston Fire Department responded with a 'big box' response and went floor by floor to make sure the gas hadn't spread.

Five people were evacuated while crews determined the source of the leak.  

Firefighters later determined it was caused by a faulty appliance.  An oven malfunctioned and released large amount of gas.  They removed the oven.