The Dutch Safety Board has identified the area from which, it said, the missile that downed Malaysia Airlines Flight MH17 was launched.
Though it declined to comment further on the exact launch site, all the territory within the 320 square kilometre area it identified was in rebel hands at the time of the July 2014 crash.
Russia has contended that if the plane was brought down by a missile, it must have been launched by Ukrainian government forces.
The Dutch Safety Board report said the Buk's impact was instantly fatal only to the three crew members in the cockpit of the plane.
The rest of the crew and the passengers died due to decompression, reduced oxygen levels, extreme cold, powerful airflow and flying objects, the report said.
But it added: “It cannot be ruled out that some occupants remained conscious during the 60 to 90 seconds before the plane crashed.”
The board said it is likely that people “were barely able to comprehend the situation in which they found themselves...no indications were found that point to any conscious actions,” such as text messages sent on mobile phones.
One passenger was found wearing an oxygen mask, but it was “unclear how the mask got there”, the board said.
Meanwhile, Dutch Prime Minister Mark Rutte has called on Russia to fully cooperate with the criminal investigation into the downing of flight MH17.
Commenting for the first time on the Dutch Safety Board’s final report, Mr Rutte said that a key priority “is now tracking down and prosecuting the perpetrators”.
He says that the Dutch Safety Board report “is a new element and undoubtedly an important building block” in the international criminal investigation that is being led by Dutch prosecutors and detectives.
Malaysia's prime minister said the world ``must move forward toward ensuring that those responsible are held accountable for this murderous act''.
Prime Minister Najib Razak said: “Fifteen months may have passed, but our commitment to bringing the perpetrators to justice remains as strong as it was on that fateful day, 17 July 2014, when hundreds of innocent people lost their lives in a conflict that was not theirs.”
Of the 298 lives lost when Malaysia Airlines Flight 17 was downed by a Buk missile, 43 were Malaysians.
The Malaysian leader also noted that no one was advised by the relevant authorities against any specific threats to aviation.
The Dutch prosecutors leading the criminal investigation into the downing of the plane say it has been tough finding eyewitnesses in eastern Ukraine to help build their case.
They say that means their probe will stretch into 2016.
In a statement released by the Dutch-led Joint Investigation Team building a criminal case to identify and prosecute the perpetrators, prosecutors say their work “depends largely on the testimonies of witnesses. It is not easy to find such witnesses, let alone to find them prepared to render a statement in a safe environment”.
The team said it has already identified “persons of interest” in the probe, but did not identify them.