Russia and Ukraine exchanged large drone attacks on Sunday night into Monday, with alleged Ukrainian UAVs forcing flight restrictions at three Russian airports.

Several apartment and administrative buildings were damaged, fires broke out. The attic floor of one of the multi-story residential buildings was partially destroyed, while a fire on the sixth floor was extinguished,

An intense video has emerged in Russia, showing a portion of a Ukrainian drone strike, including the interception of one of the drones by what is likely to have been a Pantsir short-range air defense system.

A fire erupted in the city of Kazan in Russia's Tatarstan republic overnight on Jan. 20 amid a Ukrainian drone attack on the city, Russian Telegram channels reported.

Ukrainian President Volodymyr Zelenskyy warned allies that the defense of his nation is a litmus test for broader Western resolve.

Russia's military on Tuesday said it would retaliate against Ukraine after Kyiv attacked Russian regions by firing six U.S.-made ATACMS ballistic missiles, six UK-made Storm Shadow cruise missiles and launching one of the biggest drone attacks to date.

The barrage appeared to be one of the largest recent assaults in Ukraine’s campaign to damage Russia’s war machine on its home territory.

Ukrainians conducted a drone attack on Smolensk, a city located about 306 kilometres from the Ukrainian border. The governor of the Smolensk region, Vasily Anokhin, confirmed the information about the strike.

Ukraine launched an attack using long-range drones on the Kazan Aviation Production Association named after S.P. Gorbunov (KAPO). This facility, located in Tatarstan, manufactures Russian Tu-160M strategic bombers and Tu-214 passenger planes.