KYIV, Ukraine (AP) — The Ukrainian capital Kyiv observed an official day of mourning Friday, a day after a Russian drone and missile attack on the city killed 31 people, including five children, and injured more than 150, officials said.

The death toll from Russia’s heavy bombardment of Ukraine’s capital this week has risen to 31 people, marking the deadliest single attack on Kyiv in a year, Ukrainian officials said on Friday.

A site hosting Iranian drones was among facilities struck overnight by Ukraine, according to its General Staff.