Dallas got a rather unpleasant wakeup call over the weekend: nearly 160 emergency sirens blaring throughout the city in tandem, in what Rocky Vaz, director of the city's Office of Emergency Management, says was the result of hacking from "someone outside our system" but in or near the city, per the Dallas Morning News. The 156 sirens—which Reuters notes are used to warn about dangerous weather sweeping in—started screaming at 11:42pm Friday and weren't completely turned off until 1:17am Saturday, going off for 90 seconds at a time at least 15 times, city rep Sana Syed says, per Courthouse News Service. Vaz told reporters an infrastructure hacking like this is a "very rare event" and that workers had to eventually power down the whole system when other methods of shutting off the sirens weren't working, the New York Times reports.
The Washington Post notes that jokes started circulating even as the sirens were still singing their late-night song. Some compared it to the end of the world, while Rep. Rafael Anchia put up a poll wondering if it was a Mothra versus Godzilla situation or perhaps a zombie apocalypse. But not everyone chuckled: Syed told the Times that some feared it was a bomb or missile, especially in the wake of US strikes on Syria two nights earlier. Even though the city took to Twitter to plead with locals not to tie up 911, there were more than 4,400 calls made in a four-hour span—about double what Dallas usually sees on a Friday night. Finding out what happened is now at the top of the Dallas City Council's long to-do list, with one city council member telling the Morning News, "You can put me down as terrified." (Firefighters sued a siren company for loss of hearing.)