Dozens of bodies have been found on the streets and in mass graves after Russian troops retreated from the devastated town of Bucha, laying bare the horrors of a 40-day war that has killed thousands. Ukrainian President Volodymyr Zelensky has accused Moscow of war crimes and "genocide" and is seeking stronger international pressure on Russia. The Kremlin has denied responsibility and suggested that images of the corpses in Bucha were "fakes".