“You saw what happened in Bucha,” Biden said. He added that Putin “is a war criminal.”

Biden’s comments to reporters came after Ukraine President Volodymyr Zelenskyy visited Bucha, one of the towns surrounding Kyiv where Ukrainian officials say the bodies of civilians have been found. Zelenskyy called the Russian actions “genocide” and called for the West to apply tougher sanctions against Russia.

Biden, however, stopped short of calling the actions genocide.

The bodies of 410 civilians have been removed from Kyiv-area towns that were recently retaken from Russian forces, Ukraine’s prosecutor-general, Iryna Venediktova, said. Associated Press journalists saw the bodies of at least 21 people in various spots around Bucha, northwest of the capital.

“We have to continue to provide Ukraine with the weapons they need to continue the fight. And we have to gather all the detail so this can be an actual—have a war crimes trial,” Biden said.

Biden lashed out at Putin as “brutal.”

“What’s happening in Bucha is outrageous and everyone sees it,” Biden added.

European Commission President Ursula von der Leyen, the European Commission president, tweeted Monday that he European Union will send investigators to Ukraine to help the local prosecutor general “document war crimes.

Biden noted that he faced push back last month when he described Putin as a war criminal for the unfolding onslaught in Ukraine after hospitals and maternity wards were bombed. In his remarks on Monday, Biden made clear that label still applied.

“This guy is brutal and what’s happening to Bucha is outrageous, and everyone’s seen it,” Biden said.

Investigations into Putin’s actions had begun before the new allegations of atrocities outside Kyiv.

The U.S. and more than 40 other countries are working together to investigate possible violations and abuses, after the passage of a resolution by the United Nations Human Rights Council to establish a commission of inquiry. There is another probe by the International Criminal Court, an independent body based in the Netherlands.

Meanwhile, Biden’s chief envoy to the United Nations, Ambassador Linda Thomas-Greenfield, announced Monday that the U.S. plans to seek a suspension of Russia from its seat on the U.N.’s top human rights body in the wake of more indications Russian forces may have committed war crimes in Ukraine. That would require a decision by the U.N. General Assembly.

Russia and the other four permanent members of the U.N. Security Council—Britain, China, France and the United States—all currently have seats on the 47-member-state rights council, which is based in Geneva. The United States rejoined the council this year.