As Russian and Ukrainian forces carried out fresh cross-border aerial strikes, Moscow launched nationwide nuclear drills.
Ukraine's President Volodymyr Zelenskyy said Russia launched more than 500 drones and over 20 ballistic and cruise missiles overnight, targeting multiple regions across the country.
Zelenskyy said the Russian strikes wounded more than two dozen civilians, including three children.
Four people were killed and several more were injured in the Russian missile and drone strikes in the northern Chernihiv and Sumy regions of Ukraine, according to Ukrainian officials.
A Russian overnight air strike also damaged port infrastructure in the Ukrainian city of Izmail on Tuesday.
"Fortunately, there were no casualties or significant destruction," local officials said on Telegram.
Meanwhile, drone strikes also targeted the regions of Dnipropetrovsk, Mykolaiv and Zaporizhzhia, Ukrainian authorities said on Telegram.
In the northeastern city of Kharkiv, two people were rescued and one person may still be trapped under rubble after a Russian drone attack, Mayor Ihor Terekhov said.
Moscow comes under drone attacks Meanwhile, Moscow Mayor Sergei Sobyanin said four drones approaching the Russian capital were intercepted.
Regional authorities also reported drone attacks in Russia's Kursk and Rostov.
In Kursk, bordering Ukraine, a woman has died and two people were injured in an Ukrainian attack on Monday evening, authorities said.
Ukrainian drone strikes also targeted Yaroslavl, the home of Russia's oil refining infrastructure, where industrial site caught fire, according to Governor Mikhail Yevrayev.
The latest exchanges come as diplomatic efforts to end the four-year long war remain stalled.
Russia begins nuclear weapons drills On Tuesday, Russia began three days of nationwide nuclear weapons drills involving thousands of troops.
The defense ministry said in a statement that Russian forces "are conducting an exercise on the preparation and use of nuclear forces in the event of a threat of aggression" from May 19 to 21.
The military exercise comes just ahead of President Vladimir Putin's visit to China and amid Ukraine's recently intensified drone attacks.
Massive drone attack on Russia ups pressure on Moscow To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Edited by: Dmytro Hubenko
