International investigators present their latest findings in the downing of Malaysia Airlines flight MH17, nearly five years after the crash that killed 298 passengers and crew, in Nieuwegein, Netherlands, June 19, 2019. REUTERS

The Hague, Netherlands -- An international team of investigators has named four key suspects as it builds a criminal case against those responsible for the downing of Malaysia Airlines Flight 17. The joint investigation announced the progress nearly five years after the plane was blown out of the sky above conflict-torn eastern Ukraine.

Members of the Joint Investigation Team (JIT) said in The Hague on Wednesday that three Russian nationals and one Ukrainian would be charged with murder over the attack on the civilian jet. They are suspected of facilitating the transport of the missile used to shoot down the jet from Russia into Ukraine.

Chief Dutch Prosecutor Fred Westerbeke also said investigators "have evidence showing that Russia provided the missile launcher" used in the 2014 attack.

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The Dutch-led probe identified the suspects as Russian nationals Igor Girkin, Sergey Dubinskiy and Oleg Pulatov, and Ukrainian Leonid Kharchenko. The investigators said the Ukrainian suspect was believed to be in Ukraine, but it was unclear whether the man was in the eastern part of the country still controlled by Russian-backed separatists.

All 298 passengers and crew on the flight from Amsterdam to Kuala Lumpur were killed on July 17, 2014, when a missile shattered the Boeing 777 in midair, sending debris and bodies raining down onto farms and fields of sunflowers.

The families of those killed were informed of developments in a private meeting ahead of the news conference by investigators.

"This is what we hoped for," Silene Fredriksz-Hoogzand, whose son Bryce and his girlfriend Daisy Oehlers were among the dead, said after the meeting. "This is a start of it. It is a good start."

She added that she did not expect any of the suspects to appear for the trial, due to begin in a Dutch court on March 9.

The Buk missile

The investigation team, made up of detectives and prosecutors from the Netherlands, Malaysia, Australia, Belgium and Ukraine, last year said that it was convinced that the Buk missile system used to shoot down flight MH17 came from the Russian army's 53rd Anti-Aircraft Missile brigade, based in the Russian city of Kursk.

Russia has always denied responsibility for shooting down the flight and claimed last year that the Buk missile came from Ukrainian army arsenals. The Netherlands and Australia have said they hold Moscow responsible for providing the Buk missile system used in the downing.

Kremlin spokesman Dmitry Peskov told CBS News partner network BBC News on Wednesday, before the JIT made its announcement, that there was "nothing to discuss" about the investigation's conclusions. Asked Russia would ever hand suspects over for trial or put them on trial in Russia, Peskov said the Kremlin's position was already clear.

"You know our position on this investigation. Russia had no chance to take part in it, even though from the very start -- the first days of this tragedy -- Russia... tried to be part of the investigation into this terrible catastrophe. So our position on this investigation is very well known," Peskov said.

According to the JIT, Russia has not cooperated with the investigation.

Slow-going investigation

Progress in the criminal investigation has been slow. The Joint Investigation Team, or JIT, appealed in September 2016 for witnesses to provide evidence that could help identify two men heard speaking on intercepted communications discussing movements of a convoy in the days before the attack.

At the time, the JIT said "there is no evidence that these calls are directly related to the shooting down of MH17."

The appeal said one man had the first name and patronymic Andrei Ivanovich and used the call sign "Orion" while communicating. The other communicated as "Delfin" and had the names Nikolai Fyodorovich.

Online journalism platform Bellingcat said last year it had identified "Orion" as a Russian, Oleg Vladimirovich Ivannikov, and said it had determined with "very high certainty" that at the time of the downing of flight MH17 he was an officer of the main directorate of the general staff of the Russian Ministry of Defense, known as GRU, and that he served as a military adviser to pro-Russian separatists in eastern Ukraine at the time the jet was shot down and supervised "procurement and transport of weapons across the Russia Ukraine border."

In December 2017, Bellingcat said that, based on its investigations, it had established "to a high degree of certainty" that the man known as "Delfin" is Russian Col. Gen. Nikolai Fyodorovich Tkachev. He denied having been in Ukraine in 2014.

Bellingcat published a report on Wednesday identifying more individuals it says were involved in the downing of MH17.

If Russian suspects are charged in the Netherlands, it remains to be seen whether they would ever appear for trial. The Russian Constitution bars extradition of Russian nationals for trials abroad and says that for crimes committed abroad Russians can only be tried in Russia.