Russian spies "possibly hacked" and leaked an Australian police report as part of a disinformation campaign to cover up Russia's involvement in the downing of MH17, Dutch prosecutors say.
The trial of three Russians and a Ukrainian over the murder of 298 people on the Malaysia Airlines flight, including 38 who called Australia home, is under way in the Netherlands.
Prosecutor Dedy Woei-A-Tsoi accused Russia of mounting a disinformation campaign following the disaster, and said Russian Federal Services Bureau agents had been at the missile launch site in Ukraine the day MH17 was shot down, according to a witness.
"(The witness) recognised ... that Russian military personnel were present with the Buk (missile launcher) and that he heard from his companions that people from the FSB were present at the shooting down of the aeroplane," Woei-A-Tsoi told the court in Schiphol on Tuesday.
Woei-A-Tsoi said the Russian military intelligence (GRU) probably hacked the Australian Federal Police to aid their disinformation campaign.
A Russian-linked website obtained an AFP report on the missile launcher in February but only leaked selected sections, the prosecutor said.
In the report, Australian officers initially discussed whether the photos of the Buk-TELAR missile launcher were manipulated but later corroborated their authenticity with the help of video footage.
Woei-A-Tsoi said the website selectively published only parts of the report "not to share information in a responsible, journalistic manner, but rather to spread disinformation".
None of the Joint Investigation Team members - the Netherlands, Australia, Malaysia, Belgium or Ukraine - could find the source of the leak.
"We must take into account the possibility that the published documents were obtained following a successful GRU hacking operation," she added.
AFP Detective-Superintendent David Nelson confirmed his officers had stepped up IT security since the leak, adding the disinformation campaign was not helpful to the next of kin.
"I don't think it assists their grieving and ability to follow the trial and know what the facts are," he said.
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.
Sydneysider Jon O'Brien, whose 25-year-old son Jack died on MH17, said the evidence made Russian claims about the disaster appeared "empty and ludicrous".
"It's a bit embarrassing on one level if it wasn't so offensive and had such a malicious intent," he said.
The court also heard Russian defendant Oleg Pulatov had appealed for the names to be revealed of anonymous witnesses who saw the missile being fired and the launcher being moved to and from Russia.
But prosecutor Thijs Berger said some witnesses faced repercussions for their co-operation and separatist fighters in Ukraine had recently discussed "having the green light from Moscow to execute somebody".
"Seen as whole, this information casts a dark shadow over these proceedings," Berger said.
Along with Pulatov, Russians Igor Girkin and 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.