Maxim Zmeyev / Reuters

Have Flight MH17’s crash sites been compromised?

Did pro-Russian separatists hinder the investigation in eastern Ukraine?

Malaysian Airlines Flight MH17 was presumed shot down while flying at 33,000 feet. The pieces fell to the ground in farm fields in eastern Ukraine. The debris is strewn across more than five square miles, right in the heart of a shooting war.

The territory is held by pro-Russian separatists who are fighting Ukrainian government forces and are the main suspects in the plane’s downing. And they have controlled the evidence. Many passengers on the flight were on their way to the International AIDS Conference in Melbourne, Australia. The Australian prime minister, Tony Abbott, believes something dubious occurred at the crash sites.

After the crime comes the cover-up. What we have seen is evidence tampering on an industrial scale, and obviously that has to stop.

Tony Abbott

Australian prime minister

The area was not immediately cordoned off. Onlookers and journalists were able to walk freely among the wreckage for days. There is growing international concern that the separatists possibly compromised the site. "We observed that one of the largest debris — this appears to be the big cone section to the right of the road — had somewhat been split or moved apart," said Michael Bociurkiw, spokesman for the Organization for Security and Cooperation in Europe (OSCE).

On Monday the United Nations Security Council unanimously passed a resolution calling for full and unhindered access to the crash sites. Nearly a week after MH17 was shot down, international investigators gained the rebels' permission to the sites for the first time. Near the village of Hrabove, heavily armed separatists accompanied observers from Malaysia and the OSCE.

While rebels held the crash sites, the bodies of the victims were gathered up and moved to the town of Torez. Donetsk separatist leader Alexander Borodai kept the remains in four refrigerated train cars. After a 17-hour journey from Torez, the train, carrying 198 bodies, arrived in Kiev-controlled Kharkiv, where Ukrainian authorities have set up their crash investigation center and will attempt to identify the remains.

To my dying day, I will not understand that it took so much time for the rescue workers to be allowed to do their difficult jobs and that human remains should be used in a political game … the political game that has been played with human remains, and it is despicable.

Frans Timmerman

Dutch foreign minister

The Malaysian prime minister was able to negotiate the release of the plane's two flight data recorders. Said to be in good condition, the black boxes will give the exact time, altitude and position of the aircraft when it was hit.

That the crash sites were unsecured has been a source of frustration for officials around the world. On Tuesday, Russian President Vladimir Putin said his country will do "everything in its power" to facilitate the investigation. Although he accused Ukraine and the West of escalating the conflict, the rebels and Kiev agreed to limited cease-fire zones around the crash sites.

President Barack Obama visited the Dutch embassy in Washington on Tuesday and signed a condolence book. 193 of the people who died on Flight MH17 were Dutch. He assured the people of the Netherlands that "we will work with them to make sure that loved ones are recovered, that a proper investigation is conducted and that ultimately justice is done."

That probe into the downing has begun, with teams combing the crash sites and with the data recorders now in the hands of investigators.

So many questions remain. Not least of them: Who fired at the civilian aircraft?

Did separatists with ties to Moscow compromise evidence and hinder the hunt for answers?

What needs to happen at an accident scene of this kind?

What challenges do these particular crash sites pose that may make it difficult to arrive at conclusions?

We consulted a panel of experts for the Inside Story.

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