The Malaysia Airlines MH17 flight shot down over eastern Ukraine was struck by a Buk missile brought into the conflict zone from Russia, prosecutors said Wednesday on presenting the long-awaited findings of a criminal investigation into the crash.
The Buk missile defence system was later transported back to Russia after the plane was downed, the Dutch-led Joint Investigation Team (JIT) said.
Russia responded by denouncing the international investigation as "biased" and "politically motivated."
"It has become the norm for our Western colleagues to arbitrarily designate a guilty party and invent the desired results," Russian Foreign Ministry spokeswoman Maria Zakharova said in a statement.
The Malaysia Airlines flight, en route from Amsterdam to Kuala Lumpur, crashed in Ukraine's disputed Donetsk region in July 2014 amid clashes between pro-Russian rebels and the Ukrainian military.
The incident killed all 298 people aboard, most of them Dutch.
The probe sought to determine the type and origins of the missile that downed the Boeing airliner.
The findings support conclusions drawn in a previous report that indicated the plane was hit by a Buk surface-to-air missile fired by pro-Russian rebels.
On Wednesday, investigators said in statement that they had now determined that the Buk missile had been fired from farmland near the city of Pervomaiskyi, "which, at the time, was controlled by pro-Russian fighters."
JIT investigator Fred Westerbeke said at a press conference in the Dutch town of Nieuwegein that the team had gathered ample evidence to prosecute the perpetrators in a court of law, without giving further details on where and when a trial would take place.
The United States and NATO welcomed the report.
"The team’s interim findings corroborate [Secretary of State John] Kerry’s statement in the days following the tragedy that MH17 was shot down by a Buk surface-to-air missile fired from Russian-backed, separatist-controlled territory in eastern Ukraine," US State Department spokesman John Kirby said in a statement.
NATO Secretary General Jens Stoltenberg said he welcomed the first results of the investigation, stressing that the probe is still ongoing. As the UN Security Council has concluded, those responsible should be held accountable, he said.
One-hundred investigators and public prosecutors worked on the probe to analyze thousands of pieces of debris and half a million videos and photographs, Westerbeke said.
He added that the team listened to 150,000 intercepted telephone calls. One audio intercept was played at the press conference and appeared to show pro-Russian rebels calling for the missile launch.
Russia has repeatedly urged investigators to consider evidence that Ukraine was responsible for the crash.
Kremlin spokesman Dmitry Peskov on Wednesday said Moscow has unambiguous evidence that has been ignored by the international investigation team.
Moscow analyzed radar data and found no evidence of a missile downing the airliner, Peskov announced ahead of the Dutch team's presentation, according to comments carried by Russian state news agency TASS.
"If there had been a missile, it could have been launched from other territory," Peskov said, without elaborating.