Jared Leto got stuck inside the band's LED stage box at one of their 'Monolith Tour' shows.
The 'Dangerous Night' singer was getting ready for the four panels to fly open at the start of one of the band's recent gigs, but due to a computer glitch and a low ceiling, the whole thing froze and the 'Suicide Squad' actor was forced to squeeze his way out of the container.
Speaking to Dave Berry on Absolute Radio about the blip, Jared said: "We have a lot of Spinal Tap moments just in general, we had one the other day where they got stuck.
"We start off playing inside of this box that's six LED panels and it literally lifts up into the air at an angle, the whole thing comes up and all the walls come apart.
"The other night, we played in a venue and the ceiling was really low, but something with the measurements kind of screwed up the computer and the machinery all got frozen, so the thing opened a little bit, and then just got stuck there.
"I had to push my around and slide outside of this box, but we got it working again after a minute or two."
The 46-year-old musician - who is joined on stage by his drummer brother Shannon Leto - also had to break up a fight at their gig in Cardiff last week.
He said: "I just think people got a little carried away, having a little too much fun and, you know, it's a rock and roll show so, it's not uncommon for people to get pretty passionate in the audience.
"Yeah, a little bit of passion but, you know, concerts should be a space place for everyone, and, you know, so I just stopped the show and took care of business."
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