Russian forces killed entire families, raped women in front of their children, carried out torture and looting and crushed people under tanks "for pleasure", Ukrainian president Volodymyr Zelenskiy has said.
In an address, via a translator, to the United Nations Security Council on Tuesday, he said his country had experienced the “most terrible war crimes” seen since the second World War.
Mr Zelenskiy warned that the town of Bucha was only one of many places where atrocities had allegedly been committed by occupying Russian forces.
“The massacre in our city of Bucha is unfortunately only one of many examples of what the occupiers have been doing on our land for the past 41 days, and there are many similar cities, similar places, where the world has yet to learn the full truth ... dozens of other Ukrainians communities, each of them similar to Bucha,” he said.
He compared the actions of Russian forces to those of Islamic State in territories it controlled.
Mr Zelesnkiy said he had visited the “recently liberated” city of Bucha and he said there was “not a single crime that they [Russian forces] would not commit”.
Mr Zelenskiy said the Russian troops had killed entire families and tried to burn their bodies, and that people were shot in the street or thrown into wells.
He told the Security Council women were raped and killed in front of their children, while some people had their tongues “pulled out only because the aggressor did not hear what they wanted to hear from them”.
He said: “This is no different from other terrorists such as Daesh who occupy some territories, and here it is done by a member of the United Nations Security Council.
"Today, as a result of Russia's actions in our country, in Ukraine, the most terrible war crimes of all times that we've seen since the end of World War II have been committed.
“Russian troops are deliberately destroying Ukrainian cities to ashes with artillery and air strikes, they are deliberately blocking cities, creating mass starvation. They deliberately shoot columns of civilians on the road trying to escape from the hostilities.
“They even deliberately blow up shelters where civilians hide from air strikes. They are deliberately creating conditions in the temporarily occupied territories so that as many civilians as possible are killed there.”
Mr Zelensky spoke of looting by Russian troops and of gold earrings being pulled from victims “covered with blood”.
UN secretary general Antonio Guterres warned the Security Council that Russia’s invasion of Ukraine was one of the greatest challenges ever to the international order “because of its nature, intensity and consequences”.
He said the war was putting even more pressure on the developing world, with more than 1.2 billion people particularly vulnerable to spiking food, energy and fertiliser costs.
“We are already seeing some countries move from vulnerability into crisis, and signs of serious social unrest.
UN political affairs chief Rosemary DiCarlo said it had received credible allegations “that Russian forces have used cluster munitions in populated areas at least 24 times”. She said allegations that Ukrainian forces have used such weapons were also being investigated.
“Allegations of conflict-related sexual violence perpetrated by Russian forces have also emerged. These include gang rape and rapes in front of children,” she said. “There are also claims of sexual violence by Ukrainian forces and civil defense militias.”
Russian representative to the UN Security Council Vasily Nebenzya rejected as “ungrounded” and “lies” accusations of war crimes by Russian troops in Bucha.
He repeated baseless claims Ukrainian citizens had been killed by “their own radicals” and that “Nazis” were “running the show” in Ukraine. He said there were hundreds of testimonies of cruelty against Russian speakers in Ukraine, including of torture and looting. He claimed Russian prisoners were being killed and tortured by Ukrainians.
Addressing Mr Zelenskiy, he said: “Your neo-Nazis and radicals have shown unrivalled cruelty against civilians who they use as human shields and position heavy artillery next to residential buildings and multiple rocket launchers as well. Today we have heard once again lies about Russian soldiers and military.”
Mr Nebenzya said there were “flagrant inconsistencies in events shown by Ukrainian and Western media”. He claimed that corpses found by reporters in the Ukrainian city were not there right after the withdrawal of the Russian forces – adding that this was “confirmed by several videos”.
“The corpses in no way resemble those that could be lying on the street for three or four days.”
He produced no evidence to support his claims which have been widely debunked by western media.
Also on Tuesday, Nato secretary-general Jens Stoltenberg said Russia is likely to launch a new offensive in Ukraine's eastern Donbas region in the next few weeks, adding that allies had time to help prepare the Ukrainian military.
Speaking a day before Nato foreign ministers gather in Brussels to discuss more financial, military and humanitarian support for Ukraine, Stoltenberg said Russia was planning a “very concentrated” offensive.
“We now see a significant movement of [Russian] troops away from Kyiv to regroup, re-arm and re-supply and shift their focus to the east,” Mr Stoltenberg told a news conference.
“In the coming weeks, we expect a further Russian push in eastern and southern Ukraine to try to take the entire Donbas and to create a land bridge to occupied Crimea,” he said before Wednesday’s meeting of Nato foreign ministers.
Mr Stoltenberg’s comments appeared to confirm Moscow’s announcement in late March that it was refocusing on “the complete liberation of the Donbas”, an industrial region partly under Russian-backed separatist control since 2014.
Mr Stoltenberg said it would be a new, crucial phase of Russia’s February 24th invasion, which the Kremlin calls a “special military operation”.
“Repositioning of the Russian troops will take some time, some weeks,” he said.
He said that: “In that window, it is extremely important that Nato allies provide support.”
Foreign ministers on Wednesday and Thursday are set to discuss how to send more anti-tank weapons, ammunition and medical supplies to Ukraine, Stoltenberg said.
Ukrainian foreign minister Dmytro Kuleba is expect to attend part of the two-day meeting in Brussels.
Earlier, Ukrainian president Volodymyr Zelenskiy warned worse atrocities than those discovered in Bucha are likely to be uncovered in other areas seized from Russian invaders, ahead of his appearance at the UN security council on Tuesday.
As he built support for an open investigation into the killings in Bucha, Zelenskiy said: “And this is only one town. One of many Ukrainian communities which the Russian forces managed to capture. Now, there is information that in Borodyanka and some other liberated Ukrainian towns, the number of casualties of the occupiers may be even much higher.”
The town of Borodyanka lies 25km west of Bucha.
The president accused Russia of trying to “distort the facts” about the alleged atrocities and claimed it was “already launching a false campaign to conceal their guilt in the mass killings of civilians in Mariupol”.
The scale of the killings around Kyiv is still unclear. Ukraine's chief prosecutor, Iryna Venediktova, has said 410 civilian bodies were recovered in the greater Kyiv area after Russian troops withdrew, while the mayor of Bucha, Anatoly Fedoruk, said the town had buried 280 people in mass graves because its cemeteries were under fire.
Mr Zelenskiy, who visited Bucha on Monday, said there was information to suggest more than 300 people were killed and tortured there.
The European Commission proposed on Tuesday new sanctions against Russia over its invasion of Ukraine, including a ban on buying Russian coal and on Russian ships entering EU ports, and said it was working on banning oil imports too.
“We all saw the gruesome pictures from Bucha and other areas from which Russian troops have recently left. These atrocities cannot and will not be left unanswered,” European Commission president Ursula von der Leyen said.
She said the proposal sanctions entailed an EU ban on imports of coal from Russia worth €4 billion per year, and a full transaction ban on four key Russian banks, including the country’s second-largest, VTB.
“We are working on additional sanctions, including on oil imports, and we are reflecting on some of the ideas presented by the member states, such as taxes or specific payment channels such as an escrow account,” Ma Von der Leyen said.
The EU will also ban Russian vessels and Russian-operated vessels from accessing EU ports, though there would be exemptions for agricultural and food products, humanitarian aid and energy.
The EU will also ban Russian and Belarusian road transport operators and prohibit the sale to Russia of quantum computers, advanced semiconductors, sensitive machinery and transportation equipment worth €10 billion annually.
Ms Von der Leyen said the 27-nation bloc will also stop imports of Russian wood and cement as well as seafood and liquor worth in total some €5.5 billion annually.
It will exclude Russian companies from public procurement tenders in EU countries and add further individuals to a list of people whose assets in the EU will be frozen and who will not be allowed to enter the EU.
Ukraine and Russian-backed separatist forces both reported on Tuesday that an industrial acid tank had been blown up in eastern Ukraine, creating a serious potential hazard for local people, and each pinned the blame on the other.
“In Rubizhne, Luhansk region, Russian troops hit a tank with nitric acid,” David Arakhamia, a member of Ukraine’s negotiating team at peace talks with Russia, said on Telegram.
Luhansk region governor Serhiy Haidai told residents in a message on Facebook: “Do not leave bomb shelters. If you are indoors – close windows and doors.”
Luhansk is part of the Donbas region where Russian-backed separatists have been fighting the Ukrainian army since 2014. The armed forces of the self-proclaimed, Russian-backed Luhansk People’s Republic said on telegram it was “Ukrainian nationalist formations” who had blown up the acid tank before retreating from the town.
They said it had sent up a dangerous cloud of poison gas. It was not immediately possible to independently verify the incident or to establish who was responsible. Western governments have said they are concerned that Russia or its proxies could launch a chemical attack as part of the war in and blame it on the other side. Moscow says it fears the use of weapons of mass destruction by Ukraine.
At least 11 people were killed and 61 wounded in a rocket attack on the Ukrainian city of Mykolaiv on Monday that hit a bus stop and shopping area, Ukrainian human rights ombudswoman Lyudmyla Denisova said on Tuesday.
Regional authorities had earlier said a child was among those killed in the daytime strike, which he blamed on Russian forces. Russia has denied targeting civilians.
Last week, Ukrainian authorities said at least 35 people were killed when a missile blasted a hole in the side of the regional administration building in Mykolaiv, leaving victims buried under rubble.
Meanwhile, Nato allies will discuss the delivery of more weapons to Ukraine when foreign ministers meet on Wednesday and Thursday, Nato secretary-general Jens Stoltenberg said on Tuesday.
“We speak about advanced weapons systems. We speak about, for instance, javelins and other anti-tank weapons,” he told a news conference, adding that ammunition, medical supplies and “high-end” weapons systems would also be discussed.
Meanwhile, A team from the International Committee of the Red Cross (ICRC) has been released after being held in the Ukrainian town of Manhush while trying to reach the Russian-besieged city of Mariupol.
A senior member of Ukraine’s government said the ICRC team had been freed overnight after being detained by Russian forces occupying Manhush, about 20 km from Mariupol.
“The International Committee of the Red Cross (ICRC) team that was held by police in Manhush on Monday was released last night. This is of great relief to us and to their families,” the Geneva-based ICRC said in a statement.
It said the team was focused now on “continuing the humanitarian evacuation operation” from Mariupol, where tens of thousands of residents are trapped with few supplies after weeks of bombardment by Russian forces surrounding the port city.
“This incident yesterday shows how volatile and complex the operation to facilitate safe passage around Mariupol has been for our team, who have been trying to reach the city since Friday,” the statement said.
The ICRC did not say how many of its personnel had been held in Manhush. It said last week that its team trying to reach Mariupol consisted of nine people. Ukrainian deputy prime minister Iryna Vereshchuk said the ICRC team had been sent back to the city of Zaporizhzhia, which is under Ukrainian government control and much further from Mariupol than Manhush.
“After negotiations, they were released during the night and sent to Zaporizhzhia,” she said. – Additional reporting Agencies