Russian bombers approached the Alaska coastline this week for the first time in six years but turned back after U.S. jets were dispatched to the area, officials said today.

Two Russian Bear H bombers were spotted Thursday at 4:10 p.m. (8:10 p.m. EDT) in the "outer defense identification zone," about 200 miles off the coast of Alaska and 625 miles from Anchorage, said a spokesman at the North American Aerospace Defense Command Regional Air Operations Center at Elmendorf Air Force Base.

The Russian jets remained in international airspace the entire time, said Maj. Les Kodlick. But their entry into the identification zone triggered the dispatch of U.S. jet fighters to positively identify the aircraft.

The F-15s came within 90 miles of the Russian aircraft before the Bear bombers turned away and continued traveling in international airspace.

"The important thing is that we're prepared to meet any threat," Kodlick said. U.S. officials do not know why the Russian bombers approached U.S. air space, he said.

During the Cold War, Soviet Bear bombers regularly tested U.S. air defenses, heading toward American airspace and turning aside at the last minute. The last intercept of a Russian Bear aircraft near Alaskan airspace occurred in March 1993.

On June 25, two Russian bombers were intercepted by U.S. planes over Iceland after they came within striking range of the United States. The Russian planes were on military exercises.

Defense Secretary William S. Cohen was in Russia Monday and Tuesday to shore up bilateral military ties after a months-long chill caused by NATO's 11-week bombing of Yugoslavia earlier this year.