An international investigation into the 2014 downing of Malaysia Airlines flight MH17 on Thursday released a series of phone intercepts, including one between a top aide to Russian President Vladimir Putin and Russian-controlled forces accused in the crash.
Calls between officials in Moscow and Russian-controlled authorities in eastern Ukraine mostly took place via secure telephones provided by the Russian security service, and intensified ahead of the disaster in the first half of July 2014, the Joint Investigation Team (JIT) said, according to Reuters.
"The indications for close ties between leaders of the 'DPR' ('Donetsk People's Republic') and Russian government officials raise questions about their possible involvement in the deployment of the (missile), which brought down flight MH17 on 17 July 2014," the JIT said.
MH17 was shot out of the sky on July 17, 2014, over the Russia-occupied part of eastern Ukraine as it flew from Amsterdam to Kuala Lumpur. All 298 on board died.
The Dutch-led team said the intercepts showed two leaders of the self-proclaimed 'Donetsk People's Republic' ('DPR'), who were charged with murder in June, had been in contact with Vladislav Surkov, a senior Putin aide, and Sergey Aksyonov, a Russian-appointed leader in Russian-annexed Crimea.
The Russian government, which has denied involvement in the plane's destruction, said on Thursday it could not verify the authenticity of the intercepts.
Russian Foreign Ministry spokeswoman Maria Zakharova told a news briefing in Moscow that the intercepts followed a wave of "fake news" on the subject and should be regarded with scepticism.
The Kremlin and Surkov did not immediately respond to requests for comment, Reuters said.
The investigation team published the telephone call intercepts on its website and appealed for witnesses to come forward.
In a conversation on July 3, 2014, prosecutors said Surkov indicated reinforcements would be coming from Russia: "On Saturday they are already departing for the south to be combat ready."
There were calls between Russia-controlled forces and authorities in Moscow "on a daily basis to discuss administrative, financial and military matters in the 'DPR'". The JIT released a series of phone numbers, asking witnesses to help identify the callers.
Investigators have previously found that the missile that hit the airplane originated from Russia's Kursk military base, not far from the Ukrainian border. In June, the JIT charged three Russians and a Ukrainian with 298 murders.
The four suspects are due to go on trial in absentia in a Dutch court on March 9 next year.