Investigators to pinpoint rocket launch that downed airliner over Ukraine

A surface-to-air missile hit Malaysia Airlines Flight 17 en route from Amsterdam to Kuala Lumpur, killing all 298 people aboard, most of them Dutch citizens.

At the time, pro-Russian separatists were fighting Ukrainian government forces in the region. The Boeing 777 broke apart in midair, flinging wreckage over several kilometres (miles) of fields in rebel-held territory.

The prosecutors from the Netherlands, Australia, Belgium, Malaysia and Ukraine have said they will release details of the firing location and type of BUK missile used in the attack, taking them a step closer to identifying individual culprits.

But their remit does not cover assigning blame and prosecutors would have to conduct a further investigation to use the new evidence in any future court case.

Silene Fredriksz, whose son Bryce was on the airplane with his girlfriend, Daisy, expects the investigators to say the missile was fired from the rebel-held town of Snizhne.

"We will be able to deduce whether it was Russian or Ukrainian. And I think we will just get a confirmation of what we have thought for months: that is was the prior," Fredriksz said before meeting investigators.

"This is an important step. As a family we are impatient. We want to know what happened, how it happened and why. We want those responsible to face justice," she said.

If the investigation confirms that theory, which is supported by photographic evidence and witness statements collected by Reuters, it will directly challenging Moscow's suggestion that the plane was brought down by the Ukrainian military. At the time, the nearest Ukrainian-held area was about 6 km (3.7 miles) away.

The downing played a significant part in a decision by the European Union and United States to impose sanctions on Russia over the Ukraine conflict, and East-West tensions escalated to levels not seen since the Cold War ended in 1990.

Ukrainian and Western officials, citing intelligence intercepts, have blamed pro-Russian rebels for the incident. Russia has always denied direct involvement in the Ukraine conflict and rejects responsibility for the destruction of MH17.

A civilian investigation into the cause of the July 17, 2014 incident by the Dutch Safety Board concluded last year that the airliner had been downed by a Russian-made BUK missile launched from eastern Ukraine.

Dutch prosecutor Fred Westerbeke, head of the investigative team, said earlier it had a 'long list of persons of interest' in the case and had been analysing airplane debris and ballistics found at the scene.

Prosecutors could also indicate what charges they are considering bringing - for instance criminal negligence.

Prosecutors have sought legal assistance from Moscow since October 2014, and visited in person for a week in July. "Russian authorities have offered information in the past, but have not answered all questions," they said in a statement at the time.