A bystander was shot, but miraculously saved by a glasses case in his pocket.
A journalist covering Comic-Con San Diego ended up reporting on a live police shoot-out instead.
Jeff McAdam was delivering a report from outside the Convention Center on Monday night when gunfire suddenly erupted behind him, right in the middle of the broadcast.
Insane footage captured by the Fox5 cameras show McAdam discussing the cancellation of this year's physical event in place of a virtual one, when five gunshots ring out; he spins around and attempts to continue with his report, but five more shots tell him there's something a little more pressing going on behind him.
"There's something going on in the distance... I think we have an officer involved shooting," McAdam says, backing away while the camera zooms in. "There's a shooting going on between an officer and a car that he had just pulled over... forgive us for getting out of the story that we're covering, we don't know a lot about what's going on right now or how much we want to cover it, given that we don't know the details."
His colleagues immediately ask if he is safe, which he assures them he is, even though he is only "a block away".
Zooming in, the camera catches the man hunkered down behind the front of his car, standing up to aim at the police car, before he ducks back down, removes and reloads the magazine from his gun.
"We saw this officer pull over this car about two minutes before our live hit," McAdam tells the studio. "We did see an officer backpedaling as he fired off a couple of shots and retreated... we can see him standing about 80ft behind his patrol car."
The driver could then be seen walking towards the officer with his hands in the air; he then drops his hands to his sides and then stops advancing, as the crew try to figure out what is going on.
Within minutes dozens of police cars and heavily armed officers swarmed the area; the suspect was forced to lie facedown on the ground before being taken into custody.
Harbor Police Department later told Fox it had attempted to pull over a slow moving vehicle in front of the venue, before an officer and suspect exchanged gunfire. The suspect is yet to be identified.
Police also said a bystander was hit by a stray bullet during the shootout, although they did not say from which gun.
The man escaped injury after the bullet hit a glasses case in his pocket.
Describing the scenario afterwards, McAdam relived the moment he realized his own life could be at risk — and his observation of how few people realized they were in the same danger.
"As that was all going on, there were people just walking around out here... I think a lot of people don't necessarily understand what gunshots sound like as they're happening," he said. "Didn't see anybody running... it took a few minutes for people to fully realize what was happening":