An American drone was forced down by a Russian fighter jet over the Black Sea on Tuesday, the U.S. Air Force said in a statement.

The fighter jet damaged the American MQ-9 Reaper drone’s propeller after acting in a “reckless, environmentally unsound and unprofessional manner, the Air Force said. The maneuver caused the drone to crash, the U.S. European command said.

“At approximately 7:03 AM (CET), one of the Russian Su-27 aircraft struck the propeller of the MQ-9, causing U.S. forces to have to bring the MQ-9 down in international waters,” Air Force Gen. James B. Hecker said in a statement.

Hecker is the commander of U.S. Air Forces in Europe and Africa.

“Several times before the collision, the Su-27s dumped fuel on and flew in front of the MQ-9 in a reckless, environmentally unsound, and unprofessional manner,” Hecker said. “This incident demonstrates a lack of competence in addition to being unsafe and unprofessional.”

The incident was the first known interaction between Russian and American aircraft during the Russia-Ukraine war.

The plane was a Russian Su-27, Fox News reported. It landed in Crimea after the incident.