Dallas officials blame computer hacking for setting off emergency sirens throughout the city early Saturday. Rocky Vaz, director of Dallas' Office of Emergency Management, said that all 156 of the city's sirens were activated more than a dozen times. Officials don't know who was responsible for the hacking, but Vaz said "with a good deal of confidence that this was someone outside our system" and in the Dallas area.

The city has figured out how the emergency system was compromised and is working to prevent it from happening again, he said. It's a "very concerning" issue that Dallas has never faced. Although Vaz said that identifying who sounded the sirens will be like "finding a needle in a haystack," Mayor Mike Rawlings said authorities will "find and prosecute whomever is responsible."

Mr Copper at it again

Mr Copper at it again