VIDEO: The fire that destroyed a school bus barn and dozens of buses near Waukesha is now considered arson. Agents with the Federal Bureau of Alcohol, Tobacco, Firearms and Explosives joined in the investigation Monday. Sources say the damage will be in the millions of dollars. Cell phone video shows explosions from Sunday's fire at the Dousman Transport school bus yard. The fire destroyed 34 buses and the barn. Neighbors say they felt the blasts. "As we stood along the trail and we could watch engines coming in and that. It would be like a Vietnam or some place where they were doing bombing.