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

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.

Russia’s military on Tuesday said it would retaliate against Ukraine after Kyiv attacked Russian regions by firing six US-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.

A fire erupted at an oil depot in the town of Uzlovaya in Russia's Tula Oblast following a Ukrainian drone attack on the facility overnight on Jan. 18, regional Governor Dmitry Milyaev said.

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

Ukraine used long-range drones to attack the Kazan Aviation Production Association named after S.P. Gorbunov (KAPO). These are aviation plants in Tatarstan where Russian Tu-160M strategic bombers and Tu-214 passenger planes are manufactured.

In Russia, a series of explosions occurred on the outskirts of Ryazan and Kazan. Due to an attack by strike UAVs, air defense systems are active over the cities, RBC-Ukraine reports, with reference to Russian Telegram channels and public sources.

The Borisoglebskoye experimental airfield, which houses the Kazan State Aviation Plant, the manufacturer of Tu-160 strategic bombers, was the possible target of the attack, along with the helicopter factory in the Aviastroitelny district of the city.

A fire broke out in Kazan, the capital of Russia's Tatarstan republic, early on January 20 during a reported Ukrainian drone attack, according to Russian Telegram channels. Videos circulating on social media show a large fire engulfing parts of the city,

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. Videos postedto social media appear to show a large fire ablaze following a drone attack.