Russia fired a wave of drones and missiles at Ukraine overnight, killing at least four people, Ukrainian officials said on Sunday.
The strikes came a day before Ukraine's allies were set to meet in Paris for talks on pressuring Russia to end its more than four-year war.
Ukraine's air defenses have come under strain from repeated Russian ballistic missile strikes in recent weeks.
The United States this week gave Ukraine permission to build US-designed Patriot air defense systems capable of downing Russian ballistic missiles, but it may be months before they enter production.
Three people were killed in Russian attacks on Ukraine's central Dnipropetrovsk region overnight, including two in a strike on an "industrial enterprise" in the city of Kryvyi Rig, regional officials said.
A separate drone attack on the southern city of Kherson killed a 48-year-old, mayor Yaroslav Shanko reported.
A Ukrainian drone struck a tanker as it was entering the Azov-Black Sea Canal, Yury Slyusar, governor of Russia's Rostov region, said on Sunday.
The fire caused by the attack has been brought under control and there was no risk of an oil spill because the vessel was empty, Slyusar said on messaging app Telegram, adding that there were no casualties.
The Ukrainian military has recently attacked more than 40 Russian tankers in the Sea of Azov as part of what Ukraine describes as a campaign aimed at disrupting fuel supplies to Russian forces and isolating Moscow-occupied Crimea.
Ukraine has intensified attacks on logistics and energy infrastructure in Crimea in recent weeks, contributing to fuel shortages and prompting authorities to declare a state of emergency in the peninsula.
