(NewsNation) — As Ukraine’s president bemoaned Russia’s killing of civilians to the United Nations Security Council, NATO’s secretary general warned of further atrocities Tuesday.

In an emotional appeal for the world to get serious about dealing with the attacks against Ukraine, Ukrainian President Volodymyr Zelenskyy told the Security Council Tuesday that Russian forces are deliberately killing civilians in the city of Bucha and elsewhere in the country. In his video address, he said the Russian military must be brought to justice for what he called war crimes. At times, Zelenskyy spoke so fast his translator could barely keep up.

“Citizens were crushed by cars while sitting in the road … just for their pleasure,” he said, describing the carnage.

Reports of not just the killing, but torture and rape of Ukrainian civilians by Russian soldiers have shocked and angered the world. There have been other reports of Ukrainians being forced to camps in Russia where they are stripped of their phones and IDs.

“I do not need to spell out what these so-called ‘filtration camps’ are reminiscent of,” Linda Thomas-Greenfield, U.S. ambassador to the United Nations, said. “It’s chilling — and we cannot look away.”

Zelenskyy’s meeting at 10 a.m. ET with the council came after he surveyed the damage in cities outside Ukraine’s capital, Kyiv, on Monday. Ukrainian officials said the bodies of at least 410 civilians have been found in towns around Kyiv that were recaptured from Russian forces.

“In many villages of the liberated districts of the Kyiv, Chernihiv and Sumy regions, the occupiers did things that the locals had not seen even during the Nazi occupation 80 years ago,” Zelenskyy said.

He called what is happening a genocide, and warned it could be even more widespread than what’s been seen in the images from Bucha.

NATO  Secretary-General Jens Stoltenberg on Tuesday warned of more atrocities to come in Ukraine as Russian troops retreat from areas around Kyiv.

“We haven’t seen everything that has taken place because Russia still controls most of these territories” around the capital, he said, but “when and if they withdraw their troops and Ukrainian troops take over, I’m afraid they will see more mass graves, more atrocities and more examples of war crimes.”

In the meantime, Russian President Vladimir Putin’s government is pouring soldiers into Ukraine’s east to gain control of Donbas. Russian forces are also focused on seizing the cities of Popasna and Rubizhne in the Luhansk region and the Black Sea port of Mariupol, the General Staff said on its Facebook page. Donetsk and Luhansk are controlled by Russian-backed separatists and recognized by Moscow as independent states.

The General Staff said access to the eastern city of Kharkiv, Ukraine’s second-largest city, was blocked.

“The enemy is regrouping troops and concentrating its efforts on preparing an offensive operation in the east of our country,” the statement said. “The goal is to establish full control over the territory of Donetsk and Luhansk regions.”

French President Emmanuel Macron, joining other global leaders, said there is “clear evidence of war crimes” in Bucha that demand new punitive measures.

“I’m in favor of a new round of sanctions and in particular on coal and gasoline. We need to act,” he said on France-Inter radio.

Though united in outrage, the European allies appeared split on how to respond. President Joe Biden has also said Putin should face trial for war crimes.

The U.S. is working closely with the Ukrainian Prosecutor General to collect evidence, as the international criminal court investigates. And the U.S. is expected to argue to the U.N. General Assembly that Russia should be removed from the human rights council, asking for a vote this week.

Biden is promising more sanctions, in partnership with allies, on Russia. A U.S. official who spoke on the condition of anonymity said these sanctions, including a ban on new investments in Russia, as well as toughened restrictions on the country’s financial institutions and officials, will be announced Wednesday.

“We have to hold them accountable,” Rep. Marilyn Strickland, D-Wash., said on “Morning in America.” “Later this week, Congress will be voting on the Ukraine Invasion War Crimes Deterrence and Accountability Act. This is really going to require President Biden to submit a report to Congress on the U.S. government’s efforts to collect, analyze and preserve evidence that will lead to a prosecution of war crimes for President Putin.”

Strickland said Russia’s war in Ukraine has united NATO forces against Putin.

“He has strengthened our resolve, and he has made us more united,” she said.

Russia denies it has killed any civilians. The country said the accusations are “provocation” by the Ukrainian government.