Firefighters in Tennessee were still trying to determine what caused a blaze on country music star Jerrod Niemann\'s tour bus, officials said. Niemann, his friends, father and uncle escaped the Tuesday night fire unscathed after performing at a benefit for St. Jude Children\'s Hospital in downtown Chattanooga, reported WRCB-TV, Chattanooga. \"We\'re in there and Jon [Stone] comes over and says, \'Your bus is on fire,\'\" the TV station quoted Niemann as saying. \"And I\'m like: \'Dude, your gun\'s shot. Our bus is not on fire.\' I thought it was the heater. So I went to the thermostat and it says \'Auto Cool.\' So Lee [Brice] gets off the bus and is like: \'Dude, that\'s black smoke. Your bus is on fire.\'\" Niemann said everyone immediately got off the bus, saving the musical instruments as they went, and backed away from the vehicle. \"And pretty soon we hear this, \'Boom!\' and we think it\'s the fuel line, but we look and the whole front windshield was just blown out,\" he said. \"This is where I have to say, to anyone that does not believe in God: If we were on the road driving we would\'ve never smelled it. The smell would\'ve been going down the road. It would\'ve lit up. I would\'ve been in the back room. My own father -- I don\'t care if I die, but my own father and uncle, this one night on the bus, just, no. So we\'re so, so thankful.\"