Russia fired down at least three Ukraine-launched drones targeting the country’s capital early Tuesday, according to the Russian defense ministry.

According to the ministry, its air defense systems destroyed two drones over the Kaluga and Tver regions, which border the Moscow area, as well as one over the Istra district of the Moscow region, which is closer to the city.

Moscow Mayor Sergei Sobyanin stated that the drones “were attempting to carry out an attack on Moscow,” and that a consumer services facility in the Istra district, 65 kilometers (40 miles) northwest of the Kremlin, was destroyed.

There was no damage or casualties elsewhere, the mayor defense ministry said. Reuters could not independently verify the reports.

Sobyanin said that drone debris in the Tver region fell in the Zavidovo village. According to RIA state news agency, Zavidodvo is home to “Rus”, an official residence palace of the Russian president.

President Vladimir Putin’s main residences are the Novo-Ogaryovo residence in the Moscow region as well as the Grand Kremlin Palace – where official events are held.

Russian news agencies reported that almost 50 flights were cancelled or postponed early Tuesday from the four major airports around the capital – Vnukovo, Domodedovo, Sheremetyevo and Zhukovsky.

Drone attacks on Russian targets, especially in Crimea – annexed by Moscow in 2014 – and in regions bordering Ukraine, have become almost a daily occurrence since two drones were destroyed over the Kremlin in early May.

The attacks have disrupted flights in and out of Moscow in recent weeks. Ukraine rarely takes direct responsibility for such drone strikes but says destroying Russian military infrastructure helps a counteroffensive Kyiv began in June.