(CNN) A Russian Su-30 fighter jet made an "unsafe" intercept of a US P-8A Poseidon aircraft Saturday while it was flying over the Black Sea, the Pentagon told CNN Monday.

"The US aircraft was operating in international airspace and did nothing to provoke this Russian behavior," Lt. Col. Michelle Baldanza, a spokeswoman for the Pentagon, told CNN.

The Russian jet's actions were deemed unsafe because the aircraft crossed in front of the US plane from right to left while engaging its afterburners, forcing the P-8 to enter its jet wash, an action that caused the US plane to experience "a 15-degree roll and violent turbulence," according to Baldanza.

Baldanza added that the Russian fighter jet came as close as 50 feet from the US aircraft.

She said the P-8 had its transponder on during the incident.

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