Four Russian aircraft flew in an "unsafe and unprofessional" manner near a U.S. Navy destroyer in the Black Sea, according to the Pentagon.
A defense official told NBC News that a Russian Su-24 flew within 200 yards of the USS Porter last week, flying at an altitude of just 300 feet and a speed in excess of 500 knots. The jet was armed.
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In a separate incident, two other Russian Su-24s came within 300 yards of the ship. They were not armed.
In addition, an IL-38 flew at unusually low altitude.