Ukrainian drones struck a skyscraper in the Russian city of Kazan on Saturday morning during an unusually long-range attack.
Authorities in the republic of Tatarstan, which is located 620 miles from the border with Ukraine, said there were fires in three districts of region’s capital following strikes on residential buildings.
No casualties were immediately reported but Kazan airport was closed as a precaution, according to Russia’s aviation agency.
Ukraine did not immediately comment.
Videos posted to Russian social media show a large drone exploding after hitting the upper storeys of a glass-fronted skyscraper. The 121-metre Lazurnyye Nebesa tower is the tallest building in Kazan.
State media said that at least two drones struck the same spot between the 25th and 29th floors of the “elite” residential building.
Ilsur Metshin, the mayor of Kazan, said that residents were from some properties but would not provide figures.
In a post to Telegram, Rustam Minnikhanov, the head of Tatarstan, said: “Today Kazan suffered a massive drone attack.
“While before industrial enterprises were attacked, now the enemy attacks civilians in the morning.”
Russia’s defence ministry added that the city was attacked by three waves of drones between 7.40 and 9.20am and said that it had shot down six of them.
Mr Minnikhanov’s press service later went on to say that at least eight drones were involved in the attack.
Kazan is an oil-rich city that is home to 1.3 million people and situated some 440 miles east of Moscow. Despite being deep inside Russia, it is not the first time the region has been targeted.
In April, Ukrainian drones hit an oil facility and drone factory at Nizhnekamsk and Yelabuga, two other Tatarstan towns that are more than 100 miles east of Kazan.
Earlier this year, Vladimir Putin used the city of Kazan to host a summit of BRICs leaders.
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