The long-range Tu-95 "Bear" bombers were "intercepted and visually identified" Friday morning by a pair of Alaska-based NORAD F-22 Raptors as the Russian aircraft flew in the Air Defense Identification Zone, north of the Aleutian Islands, said Canadian Army Major Andrew Hennessy, of NORAD public affairs.

The Air Defense Identification Zone extends for about 200 miles (322 kilometers) from the coastline, mostly in international airspace.

"At no time did the Russian bombers enter North American sovereign airspace," Hennessy said in a statement to AFP.

He added that the US jets monitored the Russians until the propellor-driven bombers left the Identification Zone along the Aleutians heading west.

In April last year NORAD and the Pentagon said Tu-95 Bear bombers were spotted in international air space on three occasions -- twice near the Aleutian Islands and once near mainland Alaska and Canada.

That was the first sighting of such Russian long-range bomber missions around Alaska in about two and a half years, a Pentagon spokesman said at the time.