On February 24, 2022, almost all the traffic on the M07, the main highway connecting Kyiv with western Ukraine, was heading in one direction: west. Thousands of people, most of them women and children, were fleeing Russia's invasion. Only a few were going the opposite way; one of them was Steve M., a German firefighter from the town of Borna in Saxony, near Leipzig.

Steve M. set out for Kyiv just a few hours after the bombs had begun to fall: 1,500 kilometers (932 miles) separated him from his Ukrainian wife and her son. They had only been married a few weeks; his wife and stepson were waiting to take the language test they needed to join Steve in Germany.

And then the war came.

Ambushed by shots

By the early morning of February 25, Steve had been driving for 24 hours, with almost no sleep. He was nearly at his destination when his Skoda was deliberately fired on from an ambush in Hostomel, a few kilometers outside Kyiv, and brought to a stop. Ukrainian investigators later established that the shots were fired by Russian invaders hiding in the woods, who shot indiscriminately at civilian vehicles for hours.

"The shots were fired from automatic rifles and machine guns, but also from the gun on an armored personnel carrier — everything they had," the investigator Dmytro Sitar from the public prosecutor's office in Kyiv told DW. Several hours later, this hunting of civilians had resulted in five deaths, including that of a young couple just 22 years old. Eight other drivers had managed to escape; some of them were seriously injured.

Important evidence from CCTV

The Russians had retreated to the woods on the outskirts of Hostomel after coming under artillery fire on the approach to Kyiv. Their advance was abruptly halted just outside the gates of the Ukrainian capital. The Ukrainians had blown up the bridge over the river Irpin, the final obstacle on the way to Kyiv.

When asked about a possible motive for the cold-blooded murder of civilians, Dmytro Sitar suggests that it may have been an act of revenge. "There were no warning shots; no checkpoints were set up to check vehicles. There seems to have been an order to shoot at all the cars driving past," the public prosecutor says.

Six months later, after the Russian occupiers had retreated, investigators were able to identify the shooters. First of all, the attackers were identified as belonging to a particular army unit: They were OMON fighters from the Siberian city of Krasnoyarsk.

OMON are the special forces of "Rosgvardiya," the National Guard. In peacetime, their main task is to protect the regime in Moscow from unwanted demonstrations. They had left plenty of traces of themselves in Hostomel, from individual fighters' identity cards to labels on ammunition crates.

Using facial recognition software, the investigators were able to identify five suspected OMON fighters. They had got lucky: The soldiers had been caught by several supermarket surveillance cameras, which had filmed them for hours at close range. These recordings were compared with pictures from social networks and the websites of the Russian security agencies.

The five Russians identified in this way will soon be tried in absentia in Kyiv. The investigation was a mammoth task, video evidence notwithstanding. Dozens of ballistic, photographic and forensic reports had to be meticulously prepared. Even questioning potential witnesses wasn't easy, as many had fled abroad at the start of the war — including to Germany.

Collaboration with German investigators

The firefighter Steve M. was one of those the Ukrainian investigators were able to locate months later, in Germany. His Skoda was riddled with bullets, but he managed to get out and flee. "He was lucky," says Dmytro Sitar. The Russians also shot drivers who ran to hide in the woods. A woman who stopped to try to help the injured was also attacked, Sitar says.

After his escape, Steve M. was admitted to hospital with numerous shrapnel wounds to his head. He later told German media that he fled the hospital a few days later, again escaping the Russian occupiers. He and the doctor treating him managed to get to western Ukraine, where his wife and stepson joined him shortly afterwards.

Searching for the driver of the shot-up German Skoda, Ukrainian investigators compared the car license plate with the border control database. This provided them with the driver's name. At the request of the Ukrainian prosecutor, German authorities questioned Steve M. and conveyed the victim's witness statement to their Ukrainian colleagues.

Two years on, Steve M. has been asked to testify in court in Kyiv. As Dmytro Sitar explains, Ukrainian judges can take note of written testimonies, but they are not admissible as evidence. It is not yet clear whether Steve M. will make the journey back into the warzone. He told the newspaper BILD in December that he didn't want to put himself in danger again.

Criminal proceedings in Germany — not just symbolic?

Meanwhile, a spokesperson for the German federal prosecutor's office has confirmed to DW that it too is investigating in connection with the attack on civilians in Hostomel. It has not commented on the details except to indicate that one of the victims was a German man.

In late December, Germany's federal justice minister, Marco Buschmann, told dpa news agency that investigators now knew the identities of five Russian shooters. "If we apprehend the perpetrators, we will indict them," he said. The charge: war crimes.

Gerd Hankel, an expert in international law from the Hamburg Institute for Social Research, explained to DW that, unlike in Ukraine, it is not possible in Germany to try people in absentia. The accused are most likely in Russia, and Russia does not extradite its citizens.

However, Hankel does not see the criminal proceedings in Germany and Ukraine as having mere symbolic significance.

"It sends a signal to all perpetrators: International criminal justice does not sleep. It is watching you," he says. And, he points out, crimes against humanity and war crimes have no statute of limitations.

This article has been translated from German.

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