Russian forces attacked Ukraine’s capital of Kyiv, its second largest city of Kharkiv and other centers early on Tuesday, officials said, triggering fires ​and dealing new blows to energy infrastructure.

The strikes injured four people, officials in the two largest cities said. They came on the eve of the next planned three-sided talks on resolving the nearly four-year-old war in the United Arab Emirates.

In Kyiv, as nighttime temperatures dipped close to -20 degrees Celsius (-4 degrees F), Reuters witnesses reported loud explosions after midnight, saying both missiles and drones were being deployed.

The ‌strikes caused ‌damage in five districts, hitting three apartment ‌blocks ⁠and ​a building ‌housing a kindergarten, Tymur Tkachenko, head of the city’s military administration, said on the Telegram messaging app.

Flames consumed an apartment on the upper floors of a Kyiv block in videos posted on social media. An air raid alert stayed in effect for more than five hours.