A fire broke out at a multi-story building in the Black Sea port city of Odesa late on Thursday after drones were reported to be headed for the area, authorities said.
"A high-rise building in Odesa was damaged by a downed drone," Oleh Kiper, the regional governor, said in a post on the Telegram messaging app.
He said information about casualties was being verified and urged townspeople to stay in shelters amid an ongoing drone attack.
Local Telegram channels posted photos and video of a fire that appeared to be affecting the upper two levels of a building but none immediately reported casualties.
Reuters could not independently verify the reports.