Russian state media say three MiG-31 fighter jets approached a U.S. Air Force RQ-4B Global Hawk high-altitude, remotely-piloted, surveillance aircraft over the Chukchi Sea Tuesday.

MiG-31 fighters intercepted two RQ-4B surveillance aircraft that flies over neutral waters of the Chukchi Sea. The U.S. spy drone remained in international airspace and at no time did they enter Russian sovereign airspace.

“After the RQ-4B Global Hawk spy drone moved away from Russia’s state border, the Russian fighter safely returned to its home airfield,” the National Defense Control Center said.

Also stressed that the Russian fighters’ flight proceeded in compliance with the international rules of using the airspace. No violations of the Russian state border were allowed, the National Defense Control Center stressed.

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The Global Hawk serves as a high-altitude, long-endurance, remotely piloted and unarmed, aerial reconnaissance system. The aircraft is designed to provide persistent, day and night, high-resolution, all-weather imagery of large geographic areas with an array of integrated sensors and cameras.

In addition to supporting intelligence, surveillance, and reconnaissance (ISR) requirements, the Global Hawk can be used for humanitarian assistance and disaster relief operations.