Huge Cyberattack Knocks Ukraine’s Largest Mobile Operator Offline

Ukraine’s largest mobile operator said it had come under a powerful cyberattack on Tuesday morning that knocked out service to millions of people.

The company, Kyivstar, said that the attack also affected internet access and that it was “unclear” when service would be restored. The interruption poses real danger in a country where many rely on phone alerts to warn them of impending Russian bombardments.