Russian President Vladimir Putin on Dec. 22 threatened Ukraine with "more destruction" after drones struck several buildings in the Russian city of Kazan the previous day.
Drones hit residential buildings in Kazan, located in Russia's Tatarstan region, the morning of Dec. 21. The strike shattered windows in a high-rise apartment complex, but there were no reported casualties.
Kyiv has not claimed responsibility for the attack.
"Whoever, and however much they try to destroy, they will face many times more destruction themselves and will regret what they are trying to do in our country," Putin said in a video address to the local leader of Tatarstan on Dec. 22.
The comment comes a few days after Putin on Dec. 19 threatened to launch Russia's Oreshnik intermediate-range ballistic missile (IRBM) at Kyiv to test Western air defenses.
Previously, Putin claimed Russia planned to target "decision-making centers" in Kyiv with Oreshnik missiles.
The drone attack on Kazan, which lies about 1,000 kilometers (620 miles) from the Ukrainian border, prompted school evacuations and temporary suspension of flights at nearby airports.
Officials in Tatarstan reported that of the eight drones that attacked Kazan, six struck luxury apartment buildings, one hit an industrial facility, and one was shot down.
Kyiv has targeted military and industrial facilities in Russia with drone strikes in an attempt to reduce Moscow's capacity to launch long-range weapons and finance its full-scale war against Ukraine.
Russian aerial attacks against Ukrainian cities escalated sharply in the fall of 2024. Drone strikes surged to record levels in October and November, and Russia dropped at least 100 guided bombs per day nearly every day between Nov. 1-20.
Civilian casualties from Russian missiles and aerial bombs increased significantly in 2024 compared to the previous year, the U.N. reported.
A Russian guided aerial bomb struck an oncology center in Kherson overnight on Dec. 21. President Volodymyr Zelensky called the attack "a heinous act of cruelty."