At least five Russian drones struck the northeastern Ukrainian city of Kharkiv late on Thursday and the city remained at risk, regional governor Oleh Synehubov said on Telegram.
Kharkiv Mayor Ihor Terekhov said the city's Osnovyanskyi district had been hit, triggering a fire. There was no immediate word on casualties.
Kharkiv, Ukraine's second largest city, has been a frequent target of Russian attacks in recent weeks. Russian troops launched an incursion into the northern parts of Kharkiv region last week.