He was killed by a Russian bomb while playing dominoes in Ukraine. Is this a war crime?

Video journalist Jessica Koscielniak was just getting back to her hotel room in Kharkiv, a city in far eastern Ukraine, when she heard the explosion. She looked out her window and saw smoke rising a few miles away.

Within minutes, international correspondent Kim Hjelmgaard, in a nearby room, got a call from the city's top prosecutor. Russia had just bombed a civilian apartment complex. Investigators were rushing to the scene to gather evidence of a possible war crime. The two journalists should get there, quick.

Hjelmgaard and Koscielniak grabbed their vests, helmets and gear and started out. Ambulances streaked past them, going the other way. When they got to the complex, they weren't sure where to look first. A cluster bomb, a 1980s-era Soviet-designed Smerch rocket, had detonated in the air, propelling exploding fragments in all directions. There wasn't one bomb site, but damage spread out 50 yards in each direction. Two dozen people had been hit, windows were shattered and shrapnel was everywhere.

Then they saw him. Alexander Satanovskiy, 82, lay bleeding next to a wooden table in an overgrown playground where he had been playing dominoes. They watched medics try to save him, then solemnly zip him into a body bag.

His 84-year-old widow, Anna Satanovskaya, followed as the medics carried his body to the ambulance and placed it inside. She sat on a barrier outside the doors, crying. Five people had died.

Hjelmgaard wrote: "The domino table was soaked in blood."

Anna Satanovskaya, 84, mourns her husband, Alexander Satanovskiy, after he was killed in a cluster bomb attack on a residential area of Kharkiv, Ukraine, on June 27, 2022. Satanovskiy was one of five killed in the attack.

This is a war crime, right? 

It would seem to fit.

Hjelmgaard explains that war crimes are violations of the laws of war as codified by international humanitarian treaties. They include atrocities against people or property, murder, ill-treatment, sexual violence, forced deportations, hostage killing, torture, plunder or destruction of public property, and devastation not justified by military necessity. War crimes can be committed against both civilians and soldiers. 

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Soldiers in war must try to protect civilian lives. Investigators will look for evidence that soldiers didn't do so, based on the precision of the weaponry and where it was used.

Ekaterina Bogdanova cleans Kharkiv's school No. 29 after the schoolyard was hit by a Russian missile in June.

In this attack, "the thing hit in a residential neighborhood. There are kids around; there are no military targets that nearby, probably. So if you cut it that way, you come to the conclusion there's no way that this could be anything but a war crime," Hjelmgaard says.

"But when you try to prosecute that, and certainly in an international setting, there are things that you have to prove. Did Russia make a mistake? Did it really mean to shell or fire on this residential neighborhood? You have to prove that it meant to do that. You also have to prove that there were no military targets nearby. Now we couldn't see any, but maybe there was something that we didn't see."

He says "10 out of 10 people" would probably say, "Of course it's a war crime, it's civilians being killed by, effectively, an unguided missile."

But knowing it and proving it are two different things, he says. "This cuts to the heart of some of the complications around proving  war crimes."

Who prosecutes war crimes? 

Different groups can investigate war crimes: the International Criminal Court in The Hague, Netherlands; the United Nations; or military tribunals convened by the victors after wars. Each option comes with complications. And each takes time.

Ukraine isn't waiting. As Hjelmgaard explains, the country is taking the unusual step of prosecuting war crimes in its own courts while it is still under attack.

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Ukrainian officials say they want swift justice. Some experts say local courts might give them more latitude to pursue convictions with evidence that falls short of international legal standards.

"I think they're doing the best that they can with the scenario," Hjelmgaard says. "There is no precedent for trying to trying to prosecute war crimes in an active conflict zone."

A war crimes prosecutor walks through the site of a missile strike in Kharkiv, Ukraine, June 29, 2022.

And that's why our two journalists went to Ukraine, why they spent weeks examining blast sites and interviewing witnesses. More than 1,000 Ukrainian investigators are seeking evidence like fragments of missiles, rockets and artillery shells or DNA samples from human remains.

Just how are the prosecutors doing? 

Since the start of the invasion six months ago, more than 5,000 Ukrainian civilians have died. There are now more than 26,000 war crime investigations in places like kindergartens, parks, warehouses, malls, train stations, city streets and maternity wards.

Only eight cases have been tried in Ukrainian courts.

"They are mostly lowly military guys in their late twenties who were driving a tank. One is a rape case," Hjelmgaard says. "They're POWs, essentially, that they manage to get hold of and felt that they had relatively straightforward cases."

As for the rocket strikes, like the one that killed Satanovskiy, most of these rockets are launched from Russia. Investigators gather debris as if these are crime scenes, hoping that markings found on the missiles can provide evidence. A serial number for a specific missile might someday be connected to a specific Russian military unit, identifying a specific commander who ordered the launch. 

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Time and again, our team found, prosecutors were balancing the crimes that seemed obvious against the likelihood they could be prosecuted.

As Oleksii Boniuk, who leads one of the top investigative teams, put it: "We are trying our best to manage everyone's expectations." 

The rockets land before sirens go off

The war's front line is just south and east of Kharkiv, carving out the 20% of Ukraine controlled by Russia.

Since the invasion began, Alexander Satanovskiy had heard the air raid sirens and artillery fire in the distance. Sometimes, though, the rockets land before the sirens even go off. His wife said he had taken a week off from playing dominoes, but that early evening in June he had headed back to the table with friends. 

Alexander Satanovskiy and four others were killed in a cluster bomb attack while playing dominoes at the playground table, June 27, 2022.

"She was in shock of what had happened," Koscielniak says. "It was a beautiful summer day. The light was warm and golden. You wanted to be outside. It was just gorgeous."

Anna Satanovskaya told our team about her husband. As Hjelmgaard wrote: "How he was always singing a song to himself. How he worked as a mechanical engineer in a sewing machine factory. How he was a tender and attentive husband and father. How he dreamed of someday visiting Cuba. How he had beautiful handwriting."

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Firefighters told our team not to stay long. There could be unexploded munitions on the ground. Hjelmgaard and Koscielniak knew the danger, especially that close to Russia. While in Kharkiv, they read the situation minute by minute, listening to hear if the blasts got closer, watching rocket streaks at night, wondering where they would land. 

"Especially somewhere like Kharkiv, all the stuff that falls in the sky is unguided mostly. It's old Soviet hardware and it either hits you or it doesn't," Hjelmgaard says. "So you can't really rationalize your way to a safe place necessarily. We were changing hotels all the time as we got new information.

"Are we close to any kind of infrastructure that could conceivably be a target for the Russians? Are we close to places that have been hit before? Are there any soldiers staying at our hotel? We were constantly trying to make micro decisions about how we can increase our chances of not being hit by something random. But of course, if it's random." 

For our team, this was a professional challenge. For the Ukrainians they met, it's a way of life.

The cluster bomb blast killed five and left behind people like Satanovskaya, an instant widow. “Who can punish the Russians?" she asked our team. "Please tell me?" 

Koscielniak wants her reporting to show the world these are real people, with lives and families and dreams. The story of Ukraine's war crimes is not just about the crimes but about the victims. 

"They're facing a horrific crisis," Koscielniak says. "And I think you see that in the pictures of Alexander, I think you see the realities of war and what it means to die in a war in those pictures and in the morgue. There's nothing nice or beautiful about the process of death in war. 

"There's just nothing."

“Who can punish the Russians?" asks Anna Satanovskiy, the widow of Alexander Satanovskiy.

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Nicole Carroll is the editor-in-chief of USA TODAY and president of the Gannett news division. The Backstory offers insights into our biggest stories of the week. If you'd like to get The Backstory in your inbox every week, sign up here. Reach Carroll at EIC@usatoday.com or follow her on Twitter: @nicole_carroll. Thank you for supporting our journalism. Subscribe here.