Ammonia leak spreads gas cloud

A chemical disaster unfolded in Weatherford, Oklahoma when a tanker truck carrying 25,000 pounds of anhydrous ammonia began leaking behind a Holiday Inn Express. Dozens suffered severe health injuries, and the leak led to the evacuation of over 500 area residents as authorities scrambled to contain and investigate the deadly vapor cloud. Mechanical failure in a gasket or valve is believed to have leaked the ammonia in large quantities, forming the toxic cloud that blanketed both the Holiday Inn and adjacent residential blocks.