Russian President Vladimir Putin ordered missile strikes against major Ukrainian cities on Monday in response to a Ukrainian attack on a Russian-held bridge, The New York Times reports.
An explosion on Saturday destroyed parts of the Kerch Strait Bridge, the only bridge connecting the occupied Crimean peninsula to Russia as Putin marked his 70th birthday.
Ukrainian intelligence services are believed to be behind a truck bomb that caused the explosion.
Russia on Monday responded with missile strikes against key cities, including the capital Kyiv.
The attacks killed at least 11 people and wounded at least 64 others.
The strikes also knocked out power around Kyiv and other areas.
The missiles — which also hit Lviv, Mykolaiv, Kharkiv and other cities — appeared to target energy facilities and civilian areas.
“Today, the whole world once again saw the true face of a terrorist state that is killing our people,” said Ukrainian President Volodymyr Zelensky. “Not only on the battlefield, but also in peaceful cities.”
Putin said in a televised address Monday that the military had launched “massive strike” on Ukraine’s "energy, military command and communications facilities” in response to what he described as “terrorist” actions, including the bridge attack.
"If attempts to carry out terrorist attacks on our territory continue, Russia’s responses will be tough and will correspond in scale to the level of threats posed to Russia," he said. "No one should have any doubts about this.”
Former President Dmitry Medvedev, who serves on Putin’s security council, also issued a threat.
“The first episode has been played,” he said. “There will be others.”
UN Secretary-General Antonio Guterres condemned the attack.
“This constitutes another unacceptable escalation of the war and, as always, civilians are paying the highest price,” he said in a statement.
“Shocked and appalled by the vicious attacks on Ukrainian cities,” tweeted European Commission chief Ursula von der Leyen. “Putin’s Russia has again shown the world what it stands for: brutality and terror.”
NATO chief Jens Stoltenberg also condemned Russia’s “horrific” and “indiscriminate” attacks on civilian infrastructure.
“NATO will continue supporting the brave Ukrainian people to fight back against the Kremlin’s aggression for as long as it takes,” he vowed.