Washington DC, Nov. 14 -- US Homeland Security Secretary Markwayne Mullin on Friday (local time) said authorities had found no evidence so far that a telecommunications outage which triggered a nationwide Federal Aviation Administration (FAA) ground stop was caused by a cyberattack or rogue artificial intelligence, but stressed that investigators were not ruling out any possibility.

Responding to whether he could say with 100 per cent certainty that the disruption was not caused by a cyberattack or rogue AI, Mullin said the available evidence pointed towards a mechanical failure, although investigations were continuing.

"There's nothing completely certain right now. It doesn't appear that way. We've activated our teams...This is a natio...