Russian SU-27 fighter aircraft scrambled on Wednesday to intercept U.S. Air Force RC-135 Rivet Joint spy plane flying over the Black Sea.

The Russian defense ministry reported that Black Sea Fleet SU-27 fighters were scrambled to intercept a U.S. Air Force RC-135 strategic reconnaissance aircraft as it flew close to the Crimean peninsula.

“On July 1, 2020, the Southern Air District Air Defense On-duty forces timely uncovered the operations of the US Air Force reconnaissance aircraft over the Black Sea and escorted them by Russian fighters,” it said in a statement.

Wednesday’s intercept follows similar encounters last month in which Russian fighter jets intercepted U.S. Navy and Air Force reconnaissance aircraft flight about 50 miles away from the peninsula’s Black Sea coast.

The last previous one was 26 June when SU-30 fighter jets intercepted U.S. Navy P-8A “Poseidon” patrol plane, RC-135 strategic reconnaissance aircraft, and a US air force KC-135 tanker aircraft approaching the state border of the Russian Federation over the neutral waters of the Blck Sea.

The U.S. military planes were continuously tracked by Russian radars at a considerable distance from the state border of Russia, the statement says.

“The Russian aircraft performed the flights in strict compliance with the international rules of using the airspace over the neutral waters, without violating the borders of other states,” the Russian defense ministry said.