Russian drones attacked Ukraine’s second-largest city, Kharkiv, and the southeastern city of Dnipro late on Monday and overnight, ​injuring more than 20 people, Ukrainian officials ​said.

A Russian drone struck an area near a ⁠high-rise apartment building late on Monday in Kharkiv, injuring ​seven people, smashing windows and setting cars ablaze, the ​city’s mayor and Ukrainian police said.

A second attack overnight injured four people when a drone hit a road between buildings, ​Mayor Ihor Terekhov said on the Telegram messaging app.

Kharkiv, ​located 30 km (18 miles) from the Russian border, withstood early advances ‌by ⁠Russian forces after their full-scale invasion in February 2022 and has since been a frequent target of Russian air attacks.

Ukraine’s air force said that overall, Russia ​attacked the country ​with 137 ⁠drones, of which 122 were downed or neutralised.

In Dnipro, 10 people were injured, ​including a 12-year-old boy, regional Governor Oleksandr ​Ganzha ⁠said on Telegram.

Ganzha posted photos online showing rubble in the streets and damaged building facades. City Mayor Borys Filatov ⁠said ​that at least eight high-rise ​buildings were damaged in the attack.