Ukrainian emergency personnel work at the scene of a Russian missile strike on a residential district of Kyiv on Monday. Photo by Sergey Dolzhenko/EPA

July 6 (UPI) -- At least 13 people were killed and 46 injured, five of them children, in a major Russian airborne assault on Kyiv overnight, a day before NATO heads of state and government gather for their annual summit with Ukraine a top agenda item.

Tymur Tkachenko, chief of the Kyiv City Military Administration, said search and rescue operations were underway in at least 20 locations across the capital, with missile strikes on multi-story buildings in the residential districts of Obolonskyi, Holosiivskyi, Darnytskyi and Podilskyi, where an apartment block was partially destroyed.

The State Emergency Service said three people were killed in the town of Vyshneve, just to the southwest of Kyiv, in strikes on the wider Kyiv region in which 16 people were injured. Authorities ordered the evacuation of people living near the site of the strike in Vyshneve as up to 400 emergency responders tackled a major blaze.

Kyiv Mayor Vitali Klitschko said in an online update that Tuesday had been declared a day of mourning for those killed, saying flags on municipal buildings across the city would be lowered and all entertainment events canceled.