Ukraine’s second-largest city, Kharkiv, has been struck by several drones during the country’s longest air raid alert since Russia launched its invasion.
Regional governor Oleh Syniehubov said at least five Russian drones had hit the northeastern city late on Thursday.
Mayor Ihor Terekhov said the city’s Osnovyanskyi district had been attacked, triggering a fire.
It is unclear whether there have been casualties.
Fabrice Deprez, a journalist reporting from Ukraine, said on X he had “lost count of the number of explosions shaking Kharkiv right now – a dozen or more in the past hour”.
An air raid alert lasted more than 16-and-a-half hours, public broadcaster Suspilne said – the longest alert since Russia invaded Ukraine in February 2022.
Residents were advised to stay in shelters.
Kharkiv has been a frequent target of Russian attacks in recent weeks.
President Volodymyr Zelenskyy visited the city earlier on Thursday to try to boost morale.
It comes as Ukrainian forces locked in street battles with the Kremlin’s troops in a key town in the Kharkiv region halted the Russian advance, according to military officials in Kyiv.
However, a senior Moscow official said the frontline push had enough resources to keep going.
Russian attempts to establish a foothold in the town of Vovchansk, among the largest towns in Kharkiv, “have been foiled,” Ukraine’s chief of staff said.
Six people were injured on Thursday in one Russian attack on the town using cluster munitions, local officials said, as emergency workers and volunteers were rescuing people affected by the shelling. Two medics were among the injured. Some 8,000 civilians have been evacuated from the town.
Vovchansk is just 5km (three miles) from the Russian border and has been a hotspot in the fighting in recent days.
Russia launched an offensive in the Kharkiv area late last week, heaping pressure onto Ukraine’s outnumbered and outgunned forces, which are eagerly awaiting delayed deliveries of crucial weapons and ammunition from the West.