WASHINGTON – A Russian jet collided with a U.S. Air Force drone over the Black Sea on Tuesday, causing the drone to crash after an “unsafe and unprofessional intercept,” the U.S. military reported.

The incident occurred Tuesday morning when two Russian SU-27 fighters conducted an intercept of the MQ-9 drone that demonstrated the pilots’ “lack of competence,” according to a statement from U.S. European Command. One of the fighters clipped the propeller of the drone, forcing U.S. operators to bring it down in international waters.

National security adviser Jake Sullivan briefed President Joe Biden on the incident, John Kirby, a spokesman for the National Security Council, told reporters Tuesday. Russian pilots have intercepted U.S. warplanes in recent weeks but not in such a “reckless” manner, Kirby said.

Kirby and military officials stressed that the Reaper drone was operating in international airspace when it was knocked down. The Russian fighters dumped fuel on the drone and flew in front of it before the collision.

“Our MQ-9 aircraft was conducting routine operations in international airspace when it was intercepted and hit by a Russian aircraft, resulting in a crash and complete loss of the MQ-9,” Air Force Gen. James Hecker, commander, U.S. Air Forces Europe and Air Forces Africa, said in a statement. “In fact, this unsafe and unprofessional act by the Russians nearly caused both aircraft to crash.”

“U.S. and Allied aircraft will continue to operate in international airspace and we call on the Russians to conduct themselves professionally and safely,” Hecker added.

Russian pilots have engaged in “a pattern of dangerous activity” that led up to Tuesday’s crash, according to European Command.

“These aggressive actions by Russian aircrew are dangerous and could lead to miscalculation and unintended escalation,” the statement said.

State Department officials plan to speak directly with their Russian counterparts to express concern about this unsafe and unprofessional intercept, Kirby said.

The Russian warplanes intercepted and buzzed the drone for about a half hour before the crash, Air Force Brig. Gen. Pat Ryder, the Pentagon press secretary, told reporters Tuesday. The collision damaged the Russian fighter, but it was able to land, he said.

U.S. drone operators crash landed the damaged MQ-9 into the sea, Ryder said.

The crash of the drone comes amid heightened tensions with Russia over the war in Ukraine. Since Russia invaded Ukraine in Feb. 2022, the United States has sent more than $30 billion in military aid to Ukraine.

The U.S. should not respond with direct force against Russia, said Notre Dame Law School professor Mary Ellen O’Connell, an expert on international law and the use of force.

While the drone was probably conducting surveillance for Ukraine, Russia’s disruption of the Reaper was within the laws of armed conflict, even if Russia had better ways of doing so, she said.

“The U.S. has been successful to date in assisting Ukraine without direct confrontation with Russia” O’Connell said. “That approach needs to continue.”