Russia scrambled two fighter jets on Monday to prevent two U.S. drones from violating its border over the Black Sea, the Russian Defence Ministry said.

A ministry statement on Telegram said the drones had been observed near Crimea and heading for the Russian border on an intelligence mission.

“As a result of the actions of anti-aircraft forces on duty the intelligence U.S. drones altered the direction of their flight and left the area where they were conducting air intelligence,” the ministry statement said.