BERLIN -- The U.S. military says a Russian fighter flew within 50 feet of a U.S. Navy reconnaissance jet over the Black Sea with full afterburners on, causing violent turbulence that knocked the American plane into a 15-degree roll.

U.S. European Command Spokesman Juan Martinez said Tuesday the maneuver by the Russian Su-30 jet in front of the Navy P-8A on Saturday is being treated as an "unsafe intercept."

Martinez said the P-8A was "conducting a routine operation in international airspace" at the time of the intercept.

The plane intercept is not the first close call to occur over international waters.

In May, the U.S. Navy said a Russian fighter jet flew within 20 feet of a P-8A Poseidon aircraft over the Black Sea. However, the Navy deemed it a safe encounter.

One month later, Stuttgart-based EUCOM released dramatic photos of a Russian jet coming so close to a U.S. plane over the Baltic Sea that the Russian pilot could be seen in the cockpit. The encounter was deemed to be safe by the crew.

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