Partial Source: Pwinsider
As noted earlier, several fire departments were called to the U.S. Bank Arena to deal with the small fire on the RAW stage which caused the arena to be evacuated. One person described the accident, in which thankfully no one was injured, as an "awesome, loud, frightening moment." As of 7:25EST, fans were still waiting outside, as the doors won't be opened until the company is cleared to go forward and the arena staff are back in place. A Reds game is about to take place next door to the venue, resulting in a chaotic situation outside. The show is still scheduled to go live at 8 PM, but there's no guarantee that the arena will be cleared by then at this point.
UPDATE: Fans are now being allowed inside the building. They're rushing everyone in right now.