Russian intelligence services likely hacked and leaked an Australian Federal Police report about the downing of the Malaysia Airlines flight MH17, a court has heard.

Misinformation masquerading as news allegedly spread via a Russian-linked website which had selectively published only parts of the government-held documents that questioned the authenticity of video footage of the Buk-TELAR missile launcher used in the attack.

That’s according to prosecutor Dedy Woei-A-Tsoi who told the murder trial of three Russians and a Ukrainian over the crash, which killed 298 people, that “parts of the (AFP) report that confirm the authenticity of a video were not published” to cover up Russia’s involvement in the downing of MH17.

They included an analysis of four photos of the Buk missile launcher by the AFP who initially believed were manipulated because the modified date of the files was earlier than the creation date.

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Despite the AFP being able to later corroborate its authenticity with the help of video footage, that information which was obtained in February was not published by Russian military intelligence, the GRU, the court heard.

Rather a selective batch of classified documents from the Joint Investigation Team — formed by Australia, The Netherlands, Belgium and Malaysia – served “as part of a cynical misinformation campaign that has gone on for more than five years now”, Ms Woei-a-Tsoi said.

“This website’s goal is therefore not to share information in a responsible, journalistic manner, but rather to spread disinformation,” she said.

“We must take into account the possibility that the published (AFP) documents were obtained following a successful GRU hacking operation in one of the four JIT countries mentioned above.”

An armed pro-Russian separatist standing guard near a piece of the wreckage of the Malaysia Airlines Flight MH17 after it was shot down on July 17, 2014. Photo: Getty

Russians tried to hack the Malaysian police and attorney-general’s office and the Organisation for the Prohibition of Chemical Weapons’ offices in the Netherlands to obtain information about the case, Ms Woei-a-Tsoi added in her statement to the court.

The court heard several witnesses in the MH17 trial were terrified about the repercussions of speaking out, with one witness fleeing his home in eastern Ukraine after being visited by two armed members of the GRU.

AFP Detective-Superintendent David Nelson confirmed the AFP and the wider JIT had stepped up IT security since the documents were released.

“We’ve all considered our own systems and taken the necessary steps,” he said.

Det-Supt Nelson said the incident was the only known unauthorised release of documents about the investigation.

“The prosecution service spoke about an instance of disinformation and how disinformation is being portrayed in the media and to the general public,” he said.

“I don’t wish to comment too much further on what the (Dutch) Prosecution Service said other than to say that (the disinformation campaign) is not helpful for the next of kin, I don’t think it assists their grieving and ability to follow the trial and know what the facts are.”

Bryan Clancy, who lost his brother Michael and sister-in-law Carol on MH17, said Russia had gone to unbelievable lengths to avoid scrutiny.

“They’re murderers and they’re trying to cover their tracks,” he said.

Russians Oleg Pulatov, Igor Girkin, Sergey Dubinsky and Ukrainian Leonid Kharchenko are also being tried in absentia for murder and the destruction of the civilian airliner.

The trial has been adjourned until March 23.

-with AAP