Chaos struck at least 15 malls across the country on Monday as fights broke out and false reports of gunfire spread rapidly on social media.

The disturbances — many caused by feuding teenagers, according to local authorities — disrupted post-Christmas shopping in cities in at least a dozen states.

In Elizabeth, N.J., panic broke out at the Mills at Jersey Gardens when a person shouted “gun” in response to a chair being slammed after a fight, according to a Twitter post by Mayor J. Christian Bollwage.