Shock and condemnation spread globally as Ukrainian authorities said Sunday they found the bodies of 410 civilians in the Kyiv region following the withdrawal of Russian troops.

Ukraine President Volodymyr Zelenskyy accused Moscow of committing "genocide" on a news program on U.S. network CBS. The Russian Defense Ministry denied the allegations.

Footage and images showed bodies scattered on the streets of Bucha, a town near Kyiv, and U.S. Secretary of State Antony Blinken told CNN, "You can't help but see these images as a punch to the gut."

Photo shows damage from conflict areas in the Hostomel region, as Russian attacks on Ukraine continue, on April 3, 2022 in Bucha, Ukraine. (Anadolu Agency/Getty/Kyodo)

"Since the aggression, we've come out and said that we believe that Russian forces have committed war crimes, and we've been working to document that," he said.

Ukraine officials said they had asked the International Criminal Court to probe possible Russian war crimes in Bucha and other areas near Kyiv.

The Russian Defense Ministry, however, said Russian troops had pulled out of Bucha on Wednesday, a day before it said the town's mayor had confirmed in a video address the withdrawal of Russian forces and made no mention of the deaths of civilians, according to Russia's Tass news agency.

"We strongly condemn violations of international law, such as the harming of civilians," Japanese Prime Minister Fumio Kishida told reporters Monday morning in Tokyo.

Japanese Prime Minister Fumio Kishida (L) speaks to reporters at his office in Tokyo on April 4, 2022. The day marked six months since the launch of his administration. (Kyodo) ==Kyodo

He said Japan will consider imposing more sanctions on Russia by considering the "overall situation" while working closely with the international community.

"We are deeply shocked and deem it extremely serious that many civilians have been victimized in Ukraine," said Japan's top government spokesman, Chief Cabinet Secretary Hirokazu Matsuno, in a regular news conference.

"Killing innocent civilians is a violation of international humanitarian law and is absolutely intolerable," Matsuno said. "Russia should be properly held responsible."

British Prime Minister Boris Johnson said on Twitter, "Russia's despicable attacks against innocent civilians in Irpin and Bucha are yet more evidence that (Russian President Vladimir) Putin and his army are committing war crimes in Ukraine."

U.N. Secretary General Antonio Guterres tweeted he is "deeply shocked by the images of civilians killed in Bucha" and said it is "essential that an independent investigation leads to effective accountability."

"It is time to do everything possible to make the war crimes of the Russian military the last manifestation of such evil on earth," Zelenskyy said Sunday evening in a video address posted on his official website.

Russia said in late March, when it held cease-fire talks with Ukraine in Istanbul, that its military would sharply cut back operations near Kyiv and Chernihiv, a northern Ukrainian city, as a confidence-building measure.

Human Rights Watch said Sunday it has confirmed several cases of Russian military members committing war crimes between Feb. 27 and March 14, including a case of repeated rape and two summary executions, as it interviewed 10 people, including victims, witnesses and residents.

In Bucha, Russian forces shot in the head one of a group of five men who were forced to kneel on a roadside on March 4, according to the New York-based rights group.

On March 13, a Russian soldier repeatedly raped a woman in a school in the Kharkiv region where she and her family had been sheltering, HRW said.

"The cases we documented amount to unspeakable, deliberate cruelty and violence against Ukrainian civilians," said Hugh Williamson, Europe and Central Asia director at HRW. "Rape, murder, and other violent acts against people in the Russian forces' custody should be investigated as war crimes."

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