Newly released video shows the Christmas morning explosion in downtown Nashville. The footage, recorded by a police camera, captured the fiery blast, which collapsed one building and damaged some 40 others. Another video from the CCTV system at the Nashville Downtown Hostel’s Second Avenue entrance, showed the explosion rocking the building and blowing the doors out. A recreational vehicle believed to be owned and operated by Anthony Quinn Warner blew up at 6:29 a.m. on Second Avenue in the heart of the city. Warner, 63, parked the vehicle on the street before triggering a warning that an explosion was going to happen, authorities said during a press conference on Sunday. Warner perished in the bombing, officials said. They believe he acted alone. Investigators are looking at “any and all possible motives,” Douglas Korneski, FBI special agent in charge of the Memphis Field Office, told reporters. “We’re not at a position …