The corpses and mass graves in Bucha tells the world the case against Putin at his Nuremberg will be overwhelming

The first man in civilian clothes was shot in the back of the head. You can see an inky puddle of blood by his head. His skin is a greeny-blue.

The second man, also in civilian clothes, also greeny-blue, was shot in the face at point-blank range. The hole where his forehead should be is probably the single most obscene thing I have ever seen with my own eyes. The two men have been executed. I realise that the most logical explanation for the fact that the Alsatian and the other dogs are running wild is that their owners are dead.

Two locals arrive with white plastic body bags with a zip-up front. They load each corpse into the body bag and seal them up. The sound of the zip kept on cutting into my sleep last night, like a buzz-saw in a horror movie.

The line of dead Russian tanks on Vokzalnya (Station) Street is proof that Vladimir Putin’s war is going catastrophically to the bad. Fighting war from inside the last century, the Russian armoured assault on Kyiv was slowed down here in Bucha by drones, so very 21st century, and then stopped dead in Irpin, the next town along.

When the Kremlin decided that sending yet more of its boys to die here was foolish, the Russian army hit reverse gear. As it did so, troops expressed their dismay at their wretched performance against proper soldiers by butchering innocent civilians by the hundred-fold. By the way, satellite imagery captured during the Russian occupation shows bodies on the street before the Ukrainians recaptured Bucha. The Russian army carried out these killings. Full stop.

At the centre of Bucha was a scene that we have been told would never happen again. But “never again” feels a bitter, dark joke when you look at what lies in the death pit opposite the main Orthodox Church. There’s a hand with flesh on it but the flesh has gone greeny-blue, pointing upwards. Here the body bags are black plastic.

Please note that this one is not a classic mass grave like at Babyn Yar where the killers dug a hole in the ground and shot people next to it and then covered it up. This is a mass grave where, under Russian army occupation, the dead were buried.

A trickle of Ukrainian soldiers at the start of the war, then a flood of civilians, shot or shelled or otherwise killed by Vladimir Putin’s war machine. There are around 280 corpses in this grave. Another 40 dead, like the two we’ve just seen, litter the streets and backyards of Bucha.

Russia denies everything. Its Ambassador to the United Nations, Vassily Nebenzia, has said that while Bucha was under Russian control, “not a single local person has suffered from any violent action”, adding that video footage of bodies in the streets was “a crude forgery” staged by the Ukrainians. Russia’s parliamentary speaker, Vyacheslav Volodin, said Bucha was “a provocation, with Washington and Brussels the screenwriters and directors, and Kyiv the actors”.

Overlooking the mass grave stood the local Orthodox priest, Father Andrii Holovin. You could read the shadow cast by the war in his pale, gaunt face. “They dug the first pit on 10 March.”

What do you say to the Kremlin line that you did this? His eyes look blankly at me. Don’t talk rubbish.

At the crossroads at the start of Station Street, I meet my old friend, Rabbi Moshe Azman of the Central Synagogue in Kyiv.

He tells me: “First of all, I knew what happened here before, because I was here at the start of the war. We have a Jewish community here at Anatevka. We heard what happened here. But to see the war — the cars crushed by tanks, people shot by Russian soldiers and many bodies — it’s terrible and it’s a war crime.

"The whole world just needs to stop Russian aggression. It’s like World War II but different. What is the difference? Because the Wehrmacht came, after them, the SS. And the SS, they killed people. But here, the regular Russian army, they make war and they kill people. They murder people. The world has to stop the war. It’s not only a Ukrainian problem. It’s a problem for the whole of Europe. For the whole world.”

Down the road, six members of the same family, the youngest a woman of 20, all burnt. The photos my Ukrainian colleague Alex Zakletsky takes are too horrific to share.

Not far away, a line of corpses was discovered with their hands behind their backs. Survivors have explained what happened to “Vot Tak”, a Ukrainian website. The Russians arrived in Bucha on 2 March, said Vladislav Kozlovsky, an eyewitness to some of the executions. He explained that he was in Bucha, looking after his mum and granny, when shells came down. He and his friends, all unarmed, took shelter in a basement.

The Russians blasted the first door and the people in the bunker opened the second one to try and save themselves: “The first days they treated us well, helped with food. But they were brainwashed by propaganda. Normal people do not come to a foreign land.”

As the war turned darker for the Russians, the early good conduct quickly vanished. “They would not let us out. We were sitting in complete darkness. There was no light, water, or heat.” On 7 March, the Russians made a selection, freeing the women and children but not the men. “They made us kneel and started to ‘search’ us.

They took my watch and money.” They tortured him and beat him over the head with the stock of a rifle. “If anyone had fought for the Ukrainian army in the war in the east of the country, in Donetsk and Luhansk, or were a soldier, they were shot. They shot them either in the back of the head or in the heart.”

How many people in all were killed in your presence? “Eight, I think. I saw photos of their bodies yesterday behind a stone building.”

How many of your acquaintances were killed during this time?

“I don’t divide people like that anymore, I feel sorry for everyone. An acquaintance of mine named Sergey Semyonov, who is about 40, decided to go with a friend through the glass factory to Irpin. Their bodies were found a few days later.

Sergei was killed with a shot to the back of the head. The other man was tortured. His face was cut, they finished him off with a shot to the heart. We buried them in the factory grounds.”

The prime suspects for many of the war crimes are Chechen fighters loyal to Putin’s satrap, Ramzan Kadyrov. They’re called the Kadyrovites, sport long beards, wear black uniforms. The locals in Bucha could identify them by their accents. (Please note, there are Chechens fighting on the Ukrainian side, too.)

I first saw evidence of Russian army war crimes in Chechnya in 2000: wanton killing of civilians; torture; contempt for the rules of war. Bucha is Kremlin inhumanity on repeat. The Russian army contained men from far-off Buryatia, in Siberia, Mongol soldiers, mostly Buddhist. This is Putin’s war but a lot of his drone fodder don’t come from swish apartments in Moscow.

The dark irony here is that Putin has been accused of using Chechen killers to do his dirty business for the past two decades. The assassinations of his critics, people like Anna Politkovskaya, Natalya Estemirova and Boris Nemtsov, was the work of Kadyrovites.

Now the Kremlin is faltering, stepping backwards as it faces mounting outrage from the West because its tame killers over-achieved in Bucha.

Ukraine’s President, Volodymyr Zelensky, told the UN from Kyiv: “There is not a single crime that they would not commit there. The Russians searched for and purposely killed anyone who served our country. They shot and killed women outside their houses. They killed entire families — adults and children — and they tried to burn the bodies… Civilians shot and killed in the back of the head after being tortured. Some of them were shot on the streets; others were thrown into the wells. So they died there in agony.”

What the Russians did in Bucha was no different, he said, from the conduct of Islamic State in Iraq and Syria. The difference is, the savagery was perpetrated by Russia, a member of the UN Security Council. He urged the Council to live up to its name.

“It is obvious that the key institution of the world which must ensure the coercion of any aggressor to peace simply cannot work effectively.”

Zelensky is right about that. Russia had a true claim to be at the top table at the UN in 1945. Putin has now lost the right to that table.

And Zelensky called for a new Nuremberg: “The Russian military and those who gave them orders must be brought to justice immediately for war crimes in Ukraine. Anyone who has given criminal orders and carried them out by killing our people will be brought before the tribunal, which should be similar to the Nuremberg tribunal.”

The evidence at Nuremberg Two of Russian war crimes will be overwhelming. Satellite images, drone footage, eyewitness accounts.

A cyclist on a green bike. His execution by Russian troops filmed by a drone. His body filmed by reporters when Ukrainian forces returned. Once again: Kremlin inhumanity on repeat.

The Russians have lost people too, of course, but — how to put this? — they started this monstrous war. By a single railway track lie two Russian corpses, burnt beyond recognition, their skins waxy in death. In another street, we pick our way through a charred house.

When people say that everything is destroyed, that’s not quite right. I see the burnt remains of a child’s bike, the inner tubes of a fridge. Weirdly, a gas meter remains intact while the rest of the house is charred wood and blackened bricks.

Out the back, you can see the herb garden cherished by the people who used to live there. It is a reminder of normality amid all the chaos of war and somehow all the more haunting for that.

On the way out of town, we come to yet another line of Russian tanks, fried to cinders. One of the soldiers, a Buryat, managed to struggle out of his tank but was burnt to death in its shadow. I take a photo of his scarlet sock, his bare leg tattooed.

Having seen what his fellow Russian soldiers have done in Bucha, I realise that I feel nothing for this corpse. But that would be another dark victory for Putin’s war, for Kremlin inhumanity on repeat. I force myself to think of this young man going for a walk by Lake Baikal in the spring, of drinking with his pals, of falling in love. And his mother getting a telephone call: “We are very sorry to announce...”

John Sweeney went to Bucha with Neil Camillieri, Giuseppe Attard, Alex Zakletsky and Liza Kozlenko. His podcast, Taking On Putin, is out now. You can follow him on Twitter here.