Russian authorities say three Ukrainian drones attacked Moscow in the early hours on Sunday, injuring one person and prompting a temporary closure of one of four airports around the Russian capital.

The Russian Defense Ministry referred to the incident as an “attempted terrorist attack by the Kyiv regime" and said three drones targeted the city. One was shot down in the surrounding Moscow region by air defense systems and two others were jammed. Those two crashed into the Moscow City business district in the capital.

Photos from the site of the crash showed the facade of a skyscraper damaged on one floor. Moscow Mayor Sergei Sobyanin said the attack “insignificantly damaged” the outsides of two buildings in the Moscow City district. A security guard was injured, Russia's state news agency Tass reported, citing emergency officials.

No flights went into or out of the Vnukovo airport on the southern outskirts of the city for about an hour, according to Tass, and the air space over Moscow and the outlying regions was temporarily closed for any aircraft.