Germany's intelligence service believes Malaysia Airlines flight MH17 was shot down by pro-Russian rebels using a missile taken from a Ukraine military base, a German newspaper has reported.
The finding contradicts previous claims – including by Prime Minister Tony Abbott and US Secretary of State John Kerry – that the missile was supplied by Russia.
Sunday's Der Spiegel reported that the BND, Germany's foreign intelligence service, had completed a detailed analysis of the July 17 tragedy, in which all 298 passengers and crew died.
Two weeks ago, BND president Gerhard Schindler presented the evidence to a parliamentary committee, including satellite images and photos.
The intelligence indicated that pro-Russian separatists captured a BUK missile system from a Ukrainian military base, then later fired it on MH17, Spiegel reported.
Ukraine has accused Russia of being directly responsible for the attack, and its own security service provided recordings of calls that it claimed proved the link.
In July, the head of Ukraine's SBU, Vitaly Naida, said it had "clear evidence" of the involvement of Russian citizens in the attack on MH17, which he had provided to international intelligence services.
Australian Prime Minister Tony Abbott, in his recent "shirtfront" challenge to Russian President Vladimir Putin, said those on board MH17 were "murdered with Russian support".
"I am going to be saying to Mr Putin [that] Australians were murdered. They were murdered by Russian-backed rebels using Russian-supplied equipment – we are very unhappy about this," he said.
It was not the first time he has made the claim – in August he said it was "almost indubitable that the weapon used to commit this atrocity was Russian-supplied".
Opposition Leader Bill Shorten has also said there was "plenty of evidence to indicate indirect if not direct Russian involvement in the shooting down of this plane".
In July, soon after the crash, US Secretary of State John Kerry said "an enormous array of facts ... point at Russia's support for and involvement in this effort".
And a BBC investigation for the Panorama program in September found three eyewitnesses who said they had seen a BUK launcher in the area of the crash, operated by soldiers with Russian accents.
A recent preliminary report from the official investigation of the crash, led by the Dutch, did not make any claim as to the source of the missile that brought down the plane.
Mr Schindler said his agency's "unambiguous findings" were that the missile was fired by "pro-Russian separatists".
He said Ukrainian recordings had been manipulated, but he also dismissed as false Russian claims that the missile was fired by Ukrainian soldiers, or that a Ukrainian fighter jet had been flying close to MH17.
Though the German report found that the missile used to shoot down MH17 was not supplied by Russia, there is strong evidence that Russia has supplied weapons and other support to the separatists.
A spokesman for the German Federal Prosecutor's Office told Spiegel that an investigation has been opened into unknown perpetrators because of the possibility that the crash had been a war crime.
