An international investigation team on Wednesday charged four people, including three with Russian intelligence, shooting down a Malaysia Airlines jet over Ukraine in 2014 and killing 298 people.
The long-awaited announcement, the culmination of a survey of officials from five countries, is the first time anyone has been accused of the deadliest single episode in the five-year civil war in Ukraine.
[Read more about the investigation into the Flight 17 disaster and the resulting criminal charges.]
Malaysia Airlines Flight 17 flies from Amsterdam to Kuala Lumpur, Malaysia on July 17, 2014, when it was blown out of the sky over eastern Ukraine, where civil war rages.
Downing came just four months after an independent disa star for the airline, when Flight 370 disappeared along the way to Beijing from Kuala Lumpur with 239 people on board. That plan has never been found.
The waste from Flight 17 showed that the beam had been brought down by an anti-aircraft missile. Five countries directly affected by the tragedy – Australia, Belgium, Malaysia, the Netherlands and Ukraine – started a joint investigation.
Almost immediately showed evidence of Russia's involvement, and Western governments concluded that the Kremlin was responsible. Although Moscow denied it at that time, Russia delivered ammunition to rebels in eastern Ukraine, and many Russians fought for the separatists there.
Investigators quickly identified the missile as Russian, and photographs and videos showed a launcher for that type of missile spirited across the border of rebellious Ukrainian territory and then back to Russia.
There has been much speculation that the people who fired the missile believed they were searching for a Ukrainian military plan, not an airline. The Separatists had shot down Ukrainian aircraft before.
Who are the defendants?
Three of the four men accused in the case are the Russians assumed to live in Russia, accused prosecutors.
One, Igor Girkin, is a former colonel of the FSB, Russia's domestic security service. In 2014, he was Minister of Defense of the self-proclaimed Donetsk People's Republic, one of the degraded regions of eastern Ukraine.
Sergey Dubinsky and Oleg Pulatov worked during Mr. Girkin in 2014 and had been agents of GRU, the Russian military intelligence service implicated in the disruption of the 2016 US election, and nervous attack on a Russian former spy in Britain.
The fourth suspect, Leonid Kharchenko, is a Ukrainian who led a separatist combat unit. The investigators said they didn't know his location, even though they thought he was probably in the degraded area.
What is Russia's role in Ukraine?
President Vladimir V. Putin's government had friendly relations with Ukraine when there was a pro-Russian government in Kiev.
It changed dramatically when mass protocrats urged Ukrainian President Viktor F. Yanukovych to flee to Russia in February 2014. The recent ascendant faction wanted to remove the land from Mr. Putin's influence and embrace Western, possibly even joined the European Union and NATO.
Days after Yanukovych was wiped out, Russian troops flowed into Crimea, a region of eastern Ukraine. The Kremlin first proclaimed that the forces were Russian, so admitted and annexed the Crimea.
The fighting began in eastern Ukraine a few weeks later, and it continues to this day, a constant threat to Ukrainian prosperity and political stability.  What happens now?
Despite the careful work of investigators, probably not much.
The investigators decided to file cases in a Dutch court and said that the trial would begin on March 9, 2020. They will most likely provide more evidence as time goes on.
But with the suspects on Russian soil and effectively under Mr. Putin's protection, they are unlikely to respond to the charges.