The head of the Security Service of Ukraine, Vasyl Malyuk, said a day after the strike that 41 enemy aircraft were destroyed. Other assessments, however, including one by BBC News Ukraine, tallied a more modest number, upward of 11 destroyed jets.

With 41 military aircraft impacted, the Ukrainian drone attack was described by some commentators as Russia's "Pearl Harbor." The attack on Pearl Harbor in December 1941 was a surprise air raid by Japan on the U.S. during World War II. Kyiv's assault follows ground advances by Moscow troops in recent days in Ukraine's Sumy border region.

It also roughly tallies with attempts by Russian independent media, such as Meduza and Mediazona, to count the bodies. By this time last year, Meduza reckoned that between 106,000-140,000 Russian soldiers had died. Much of their analysis was based on inheritance records and obituaries on social media and in other outlets.

The drone strikes on Russian air force bases weaken Moscow’s ability to wage war on its neighbor and undermine its capacity to threaten more distant rivals.

Ukraine has carried out large-scale drone strikes against four airbases deep inside Russia, destroying multiple combat planes, according to a source in the Ukrainian Security Service (SBU).

(Reuters) -Two bridges collapsed in different Russian regions bordering Ukraine, derailing trains and killing at least seven people and injuring dozens, Russian authorities said early on Sunday, while a Russian politician called Kyiv a "terrorist enclave".