Waves of Russian missiles strike civilian targets across Ukraine in deadly overnight attack

KYIV and LONDON -- Russia's military struck cities across Ukraine overnight, sending waves of missiles and drones in an hourslong attack that Ukrainian officials said may be among the biggest since the war began nearly two years ago.

The Ukrainian Air Force said it's "never seen so many locations targeted simultaneously."

The aerial attack began at about 11 p.m. on Thursday and lasted for several hours. It included at least 122 missiles and 36 drones, the Ukrainian Armed Forces said.

Civilian hubs, including Kyiv, were among the targets, military officials said. At least 31 total deaths were reported in at least three cities, with many others injured, local officials said.

"We will surely respond to terrorist strikes," Ukrainian President Volodymyr Zelenskyy said on social media. "And we will continue to fight for the security of our entire country, every city, and every citizen. Russian terror must and will lose."

The attack hit targets including a "maternity ward, educational facilities, a shopping mall, multi-story residential buildings and private homes, a commercial storage, and a parking lot," Zelenskyy said.

Along with Kyiv, the cities Russia struck included Lviv, Odesa, Dnipro, Kharkiv and Zaporizhzhia, he said.

"Unfortunately, there have been fatalities and injuries as a result of the strikes," he said. "All services are working around the clock and providing the necessary aid. My condolences to those who have lost their loved ones. I wish a speedy recovery to those injured."

President Joe Biden condemned Russia's aerial bombardment of Ukraine overnight, and urged Congress to pass additional aid for Ukraine.

"Strikes reportedly hit a maternity hospital, a shopping mall, and residential areas -- killing innocent people and injuring dozens more. It is a stark reminder to the world that, after nearly two years of this devastating war, Putin's objective remains unchanged. He seeks to obliterate Ukraine and subjugate its people. He must be stopped," Biden wrote in a statement.

Biden noted that Ukraine was able to deploy their air-defense systems to intercept some of the missiles, thanks to support from America and other allies, but warned that the help has run out.

"The American people can be proud of the lives we have helped to save and the support we have given Ukraine as it defends its people, its freedom, and its independence. But unless Congress takes urgent action in the new year, we will not be able to continue sending the weapons and vital air defense systems Ukraine needs to protect its people. Congress must step up and act without any further delay."

The United Kingdom will send "hundreds of air defense missiles to restock" the British air defense systems given to Ukraine, the U.K.'s Secretary of State for Defense Grant Shapps announced in a post on X, the platform formerly known as Twitter, after Russia's attacks on Ukraine.

"Putin's latest wave of murderous airstrikes are a desperate and futile attempt to regain momentum after the catastrophic loss of hundreds of thousands of conscripts and ahead of the humiliation of his three-day war entering a third calendar year," Shapps said in his statement.

On Dec. 29, 2022, the Russian military launched 70 missiles over Ukraine, marking one of the biggest missile attacks on Ukraine at the time. Ukrainian officials downed 58 of those missiles, they said at the time.

ABC News' Joe Simonetti and Molly Nagle contributed to this story.