(Reuters) -Alaska Airlines said it has canceled 7% of its flights Monday in the aftermath of a ground stop late Sunday prompted by the unexpected failure of a critical piece of hardware at its data centers.

Alaska said it has canceled 64 flights Monday and more than 150 in total since Sunday evening after it halted all flights for about three hours over the IT issue before resuming operations around 11 p.m. PDT.

"Additional flight disruptions are likely as we reposition aircraft and crews throughout our network," Alaska said in a statement. "The IT outage is not related to any other current events, and it's not a cybersecurity event."