There were cases when enemy drones shot down army aviation helicopters, such as Mi-24.

The Ukrainian military intends to launch anti-aircraft missiles at Russian drones flying from the illegally annexed Crimea.

"If we are talking about quadrocopter drones, it's sufficient to use small arms, namely machine guns. If we are talking about serious UAVs of the Orlan or Forpost type, then anti-aircraft missiles are used in this case. Buk-M1 was often used against these drones, since there was a significant threat to our military. There were cases where enemy drones would shoot down army aviation helicopters, such as Mi-24s," said press secretary of the Command of the Air Forces of Ukraine Yuriy Ihnat, RFE/RL's Krym Realii reports.

UNIAN memo. Russia annexed Ukraine's Crimea in March 2014 after its troops had occupied the peninsula. An illegal referendum was held for Crimeans to decide on accession to Russia. De-facto Crimean authorities reported that allegedly 96.77% of the Crimean population had voted for joining Russia.

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On March 18, 2014, the so-called agreement on the accession of Crimea and the city of Sevastopol to Russia was signed in the Kremlin. The West did not recognize the annexation in response to which sanctions against Russia were introduced.

Ukraine's parliament voted to designate February 20, 2014, as the official date when the temporary occupation of Crimea began.