Russian troops have seized their first major Ukrainian city and are laying siege to other urban areas, one week after President Vladimir Putin ordered an invasion. Russia’s military took over the strategically located southern port city of Kherson on Wednesday; meanwhile, missiles and heavy artillery fell on the cities of Mariupol, Chernihiv and Kharkiv.

On Wednesday, Russia’s military acknowledged for the first time that hundreds of Russian soldiers have died in the invasion.

Igor Konashenkov: “Four hundred ninety-eight Russian servicemen died in the line of duty. All possible assistance is being provided to the families of the deceased. One thousand five hundred ninety-seven of our comrades were wounded.”

A Ukrainian official put Russia’s toll far higher, claiming 7,000 troops have been killed, with hundreds more taken prisoner. The United Nations says 227 civilians have been killed, though that number is certain to rise.