A loud noise that sparked a stampede at Saturday's Global Citizen Festival in New York City's Central Park turned out to be the popping of plastic bottles, a New York Police Department source tells ABC News. The loud sound was mistaken for gunfire by some patrons, leading thousands to rush for the exits; a dozen people sustained injuries in the ensuing panic. The New York City Police Department confirmed to ABC News that the loud noise, originally reported as being caused by a fallen security barrier, "was the sound of an attendee(s) stepping on and popping a drink bottle(s).“ In a statement to ABC on Sunday, Global Citizen's Hugh Evans said that sometime after 7 p.m., some attendees heard "a loud noise" they believed to be gunshots and raced to exit the park. Coldplay frontman Chris Martin, along with NYPD Assistant Chief Kathleen O'Reilly, took the stage to reassure the understandably frightened crowd: "You're all safe," according to USA Today. "What happened is a barrier I think fell down...But nobody is trying to hurt anybody," Martin continued. "Of course everyone is worried, we all care about people." "There's no need to run fast," he warned, according to the newspaper, adding, "There's no need to push people out of the way." The concert -- which also featured The Weeknd, Shawn Mendes, Cardi B, John Legend, Janelle Monáe and Janet Jackson -- was paused until police were able to restore order. Global Citizen is a movement to end extreme poverty by 2030. More than 60,000 people have attended the festival since its debut in 2012. Copyright © 2018, ABC Radio. All rights reserved.