Ukrainian forces destroyed dozens of Russian warplanes with a drone attack on air bases deep within Russian territory on Sunday.

Ukrainian forces successfully destroyed 40 aircraft in an attack that, according to an official, took over a year to plan. Russia’s defense ministry acknowledged the attack on Sunday, stating that it targeted five airfields.

Drones were reportedly transported in containers by trucks deep into Russian territory for the operation. The drones are said to have hit 41 planes stationed at various airfields on Sunday afternoon, including A-50, Tu-95, and Tu-22M aircraft, as mentioned by the official.

Previously, Moscow has employed Tupolev Tu-95 and Tu-22 long-range bombers to launch missiles at Ukraine. The A-50 aircraft are utilized to coordinate targets and detect air defenses as well as guided missiles.

A series of explosions also struck bridges in Russia near Ukraine’s border on Saturday, though Ukraine has not taken responsibility for the attacks.

Ukrainian soldiers from the 115th Brigade Mortar Unit conduct mortar training, as members of the Anti-UAV unit test an FPV drone inhibitor in Lyman, Ukraine. (Jose Colon/Anadolu via Getty Images)

A highway bridge over a railway in the Bryansk region was blown up at 10:50 pm (1950 GMT) on Saturday night just as a passenger train carrying 388 passengers to Moscow was passing underneath, Russian investigators said.

Just four hours later, a railway bridge over a highway was blown up in the neighboring Kursk region, showering the road with parts of a freight train, the investigators said.

Fox News’ Sarah Tobianski, Reuters and the Associated Press contributed to this report.