Doja Cat was performing at a concert in Indianapolis Saturday night, when the impatient fan wanted to cut the line to get inside.

A Deputy Police Chief told the IndyStar, "A fan wanted to advance in line so he exercised very poor judgment and told those around him in line he had a bomb in his backpack."

Cops were called and no explosives were found, but the guy was arrested for unrelated, outstanding warrants.

It's always insane for anyone to make such a threat, but especially in these times... and not just because of the political landscape. After the Astroworld tragedy, lots of people are on edge at concerts, so something like this predictably will cause chaos.

A concertgoer posted this ...  "Just waited 4 hours to see doja cat for their [sic] to be a literal bomb threat(???) scariest moment of my actual life the ground was covered in ice we were all running and slipping around literally so scary."

A fan was also freaked out ... "We were considering leaving before the bomb threat happened. Saw the front of the line push everyone back and dipped out of there. Not going back."

By the way ... another, smaller incident once the concert began. Doja Cat stopped the show for a short while because 2 fans were fighting.