Two people are fighting for their lives after they were left critically injured by a fire that broke out at the Austin City Limits Festival in Texas on Friday afternoon (14Sep07). Fire officials took 40 minutes to contain the blaze, which is believed to have started when a propane tank exploded in a food vendor area between two of the festival's stages in the city's Zilker Park. Billboard.com reports the two critically injured people were transported to the Brooke Army Medical Center in San Antonio. Two more injured people were also treated. Singer/songwriter Pete Yorn was performing when the blaze started. His set was halted as fire officials fought the flames.