Relatives of victims killed in the 2014 downing of a passenger jet over Ukraine are marking the anniversary of the tragedy, an incident that international investigators have blamed on Russia and the separatist forces it backs in the region.

Dozens of family members and other dignitaries gathered on July 17 near Amsterdam's main airport at a monument where the names of those killed in the downing of Malaysian Airlines flight MH17 were read aloud.

In all, 298 people died, 193 of them Dutch citizens, when the airliner flying between Amsterdam and Kuala Lumpur was shot down by an antiaircraft missile over territory controlled by Russia-backed separatists.

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In Malaysia, nine embassies whose citizens were killed were scheduled to hold a memorial service; 43 Malaysians died in the incident. Other victims came from countries including Australia, Canada, Britain, and Belgium.

Mourners at the Dutch monument were surrounded by 298 trees -- one was planted for each victim -- and sunflowers grown from seeds from the Ukrainian fields where the wreckage fell.

In Malaysia's capital, Kuala Lumpur, relatives of the Malaysians on board lit five large white candles to mark the anniversary and observed a minute of silence at a ceremony jointly organized by the Australian and Dutch embassies that featured 298 sunflowers.

Investigators from the Dutch-led Joint Investigative Team have concluded that a Russian military brigade transported a Buk missile system to and from Ukraine, across the border with Russia.

In June, the team accused three Russians with military and intelligence backgrounds and a Ukrainian man with no prior military experience. Those included Igor Girkin, a retired colonel from Russia's main intelligence agency, the Federal Security Service (FSB). He has dismissed the accusations.

The four are scheduled to be put on trial for murder in the Netherlands starting in March 2020, though all are believed to be in Russia and are unlikely to be extradited.

In London, British Foreign Secretary Jeremy Hunt paid tribute to the victims on July 17 and announced that Britain will offer financial support for the establishment of a special criminal court in the Netherlands that will hear the trial of the four suspects.

Moscow has repeatedly denied any involvement.

The Downing Of MH17: What Happened?

On the eve of the anniversary, George Kent, a top official at the U.S. State Department, pointedly blamed Moscow.

"Russia set the stage for the shootdown of MH17 by financing, organizing and leading proxies in eastern Ukraine," Kent said, speaking in Washington.

"Russia continues to deny the presence of its forces and materiel" in non-government-controlled parts of Ukraine, he said.

U.S. State Department spokeswoman Morgan Ortagus called on Moscow "to ensure that individuals currently in Russia who were indicted by Dutch prosecutors in June will face justice."

Western countries imposed economic sanctions on Russia after the incident, which came three months after full-scale fighting broke out in eastern Ukraine.

Infographic: MH17 By The Numbers (click to view)

Dutch prosecutors might get to question a possible witness after Ukrainian special forces on June 27 apprehended a Ukrainian man who was allied with separatists and who oversaw an air-defense unit in a town near where the jet came down.

Volodymyr Tsemakh's lawyer and his daughter have confirmed his arrest, and told Ukrainian media he had been charged with terrorism.

TV footage obtained by Current Time, the Russian-language network led by RFE/RL in cooperation with VOA, showed Tsemakh claiming that he was in charge of an antiaircraft unit and that he helped hide the missile system in July 2014.

He also shows the interviewer where the civilian airliner fell.

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Also on July 17, an official with the Ukrainian Security Service (SBU) identified a man who worked as the driver of the truck that transported the Buk missile.

Vitaliy Mayakov, deputy chief of the SBU's Main Investigation Department, told reporters that the man had been detained, and convicted on terrorism charges in 2017. He did not identify the man.

Asked why officials waited two years to announce the arrest, Mayakov said the information had been classified for security purposes.

Despite Russia's repeated denials, open-source researchers and reporters have turned up substantial evidence bolstering the Dutch investigative team's finding about Russian involvement.

In the hours after the plane's wreckage fell over a wide area in eastern Ukraine on July 17, 2014, Russian media, along with Moscow-controlled media in the parts of eastern Ukraine controlled by separatist forces, reported that separatists claimed to have downed a Ukrainian military plane around the same time when MH17 was destroyed.

With reporting by Todd Prince in Washington, Current Time, AFP, and the Kyiv Post