Two Russian long-range bombers were intercepted off the coast of Alaska by a pair of F-22 Raptor fighter jets on Friday, the military said.

The Tu-95 bombers were flying in the Air Defense Identification Zone in the Bering Sea north of the Aleutian Islands, where they were visually identified and shadowed by the U.S. jets at 10 a.m., said Navy Capt. Scott Miller, a North American Aerospace Defense Command spokesman.

The bombers did not enter North American sovereign airspace, he said in a statement. Miller declined to say how close the bombers came to U.S. land. Fox News reported they flew as close as 55 miles off Alaska’s west coast.

Friday’s encounter was the first of its kind in just more than a year, Miller said. A similar incident occurred off Alaskan waters in April 2017 in what U.S. officials have described as routine if not tense encounters between adversarial aircraft where territorial lines meet.

[The Navy is resurrecting a fleet to protect the East Coast and North Atlantic from Russia]

The identification zone extends about 200 miles off the Alaskan coast and is mostly international airspace, Miller said, though Russian military activity will often prompt an in-kind response for U.S. warplanes. Intercepts in the zone occurred about 60 times from 2007 to 2017, the New York Times reported last year.

Miller said the Russian bombers, decades-old aircraft classified by NATO as the “Bear,” were flying in accordance with international norms. The aircraft are capable of carrying nuclear bombs, but it unclear what weapons they had on board, if any.

A Russian Defense Ministry statement released Friday diverged from the U.S. military account. They said the bombers were escorted by fighter jets and a reconnaissance jet that also acts as an anti-submarine platform.

Miller said that was not true.

“This was a safe intercept, which did not include a Russian recon plane, and no Russian fighters were present,” he told The Washington Post on Saturday.

It was not clear if the Russian air operation was an opportunity for real-world training or if it was in response to U.S. and NATO military operations elsewhere. Last week, Russia scrambled jets four times in response to foreign reconnaissance flights near its border, the Russian news service Interfax reported.

Aircraft intercepts, flybys and shadowings have escalated in recent years after Russian military activity and occupation in Crimea and parts of eastern Ukraine beginning in 2014.

Earlier this month, a Russian Sukhoi Su-27 fighter jet flew within 20 feet of a U.S. P-8 surveillance aircraft over the Baltic Sea — a minuscule distance considering the aircraft move at hundreds of miles an hour — in an incident the U.S. military called safe but unprofessional.

[The Pentagon answered some questions about the Niger ambush. Many more remain.]

Friday’s incident was relatively routine, but more aggressive maneuvers have worried defense officials and diplomats who said the encounters may eventually cause collisions or miscalculations that lead to a shoot-down.

A report issued in 2014 by the European Leadership Network, a London-based think tank, documented almost 40 incidents that together “add up to a highly disturbing picture of violations of national airspace, emergency scrambles, narrowly avoided midair collisions, close encounters at sea, simulated attack runs, and other dangerous actions happening on a regular basis over a very wide geographical area,” according to the report. The report was only compiled for 2014 and not for the subsequent years.

Rick Noack contributed to this report.

Read more:

Military investigation of Niger disaster finds numerous failures in planning

Missing for 48 hours: Pentagon details Army sergeant’s final moments in Niger