Russia’s military says it captured more than 1,000 Ukrainian marines defending the besieged city of Mariupol after they surrendered on Wednesday. Videos broadcast on Russian state TV appear to show Ukrainian soldiers marching with their hands up. Ukrainian officials have not verified Russia’s claim of a mass surrender. Russian troops have moved into the city center of Mariupol, where some 100,000 civilians remain trapped, with no power, water, telephone or internet access, and dwindling supplies of food and medicine. This is Valentina, an elderly Mariupol resident who’s survived weeks of heavy assaults.

Valentina Pletnyova: “Why are they killing us? Why are they destroying us? Why do this to our houses? Three 10-story buildings were burnt completely. People are sitting in the basement. There is no sewer there. Plastic tubes started burning. One bay of the 10-story building crumbled. Nineteen people dead.”

On Thursday, Mariupol’s mayor accused Russian troops of bringing mobile crematoria to the city to burn the bodies of civilians killed during Russia’s assault. Meanwhile, Russia’s Black Sea naval flagship has been heavily damaged in an explosion. Russia claims a fire aboard the vessel caused ammunition to explode, while Ukraine says it launched a successful missile attack on the ship.

On Thursday, the Biden administration authorized another $800 million in new military aid to Ukraine, including howitzers and armored personnel carriers.