Russian President Vladimir Putin has pledged retaliation after Ukrainian drones struck residential buildings in the city of Kazan in Russia’s Tatarstan region. Putin made the comments via videolink on Sunday while addressing the local leader of Tatarstan in a road-opening ceremony. “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. -snip- Kazan is more than 1,000km (600 miles) from the Ukrainian border.