Updated

A year since a Malaysia Airlines Boeing 777 was blown out of the sky over war-ravaged eastern Ukraine — killing 298 people — there has been little official word of progress in determining what brought down Flight MH17. One of the probes under way reportedly points toward a ground-to-air missile fired from a village held by Russia-backed separatist rebels, but the report isn't to be public for months. Another investigation trudges forward with painful slowness, and contradictory theories emerge from Moscow.

A fog of vehement allegations, macabre claims and self-serving rhetoric shrouds the tragedy.

Within hours of the July 17, 2014 crash, a crucial fact appeared clear — the wreckage was strewn over such a wide area that the plane must have broken into bits long before it fell. Most evidence points to the plane, which departed from Amsterdam en route to Kuala Lumpur, Malaysia, being taken down by a missile over an area controlled by pro-Russia rebels.

But whether the missile was fired from a warplane or from the ground remains unclear. As is the question of who fired: the Ukrainian army, the separatist rebels or Russian forces allegedly backing them with troops and arms. An international investigation may be able to answer the first question, but not until at least October. Another probe addressing the second is likely to take until at least next year.

A look at where the investigations and theories stand:

CRASH CAUSE

The investigation led by the Dutch Safety Board aims only to determine the crash cause, not to ascribe blame. That's likely to produce a report loaded with esoteric technical detail. A preliminary report from the board in September was able to say only that the plane was destroyed by "high-energy objects" that pierced it from outside.

A draft version of the final report was circulated this month to representatives of Malaysia, Ukraine, the U.S., Russia, Britain, Australia and the Netherlands for their comments and suggested revisions. Oleg Storchevoi, a deputy chief of the Russian aviation agency, said the agency has complaints regarding both the technical data and the arguments in the report. He did not give details.

But a U.S. official told The Associated Press that the draft says the plane was destroyed by a Russian-made Buk surface-to-air missile fired from the village of Snizhne, which was under rebel control. The official, who wasn't authorized to comment publicly, spoke on condition of anonymity.

The probe is being led by The Netherlands because 196 of the victims were Dutch, and Ukraine agreed to give Holland formal responsibility for the investigation.

CRIMINAL INVESTIGATION

A probe by the Dutch national prosecutor's office aims to establishing who was responsible. This investigation includes authorities from Ukraine, Malaysia and other countries whose nationals were among the victims, but Russia is not a participant.

It is unclear whom the investigators are questioning, or the extent of the evidence they've collected. The prosecutor's office released a video calling on witnesses to come forward and indicated the probe is focusing on rebel or Russian involvement. The video asks for information about a Buk-11 missile system that was spotted moving through the rebel territory before and after the crash, then possibly heading for the Russian border. The investigative organization Bellingcat also has devoted attention to this missile-launcher, claiming it can be traced to one that was stored in the rebels' main stronghold of Donetsk.

Rebel officials at the time denied having any such missile systems, although Russian news agencies had reported rebel claims of seizing some from Ukrainian forces a few weeks earlier.

Russia is opposing a proposed UN Security Council resolution to establish an international criminal tribunal for the crash; Moscow has veto power in the security council.

RUSSIA'S THEORIES

A few days after the crash, the Russian Defense Ministry showed photos it said proved that Ukrainian surface-to-air systems were operating in the area before the crash. Russian officials also said they had evidence that a Ukrainian Su-25 fighter jet had flown "between 3 to 5 kilometers (2 to 3 miles)" from the Malaysia Airlines jet.

The latter theory was revisited a few months later when state television released a satellite photograph that it claimed showed that a Ukrainian fighter jet shot down MH17. The photo purportedly came from a little-known person who identified himself as an aviation expert. Bloggers following the case quickly claimed the photo was a forgery.

In June, the Russian manufacturer of Buk systems said it had concluded the airliner was indeed brought down by a Buk, but an older model no longer in service in Russia. It said such systems were still used by the Ukrainian army, but it was not clear if the Buks reportedly seized by rebels a year earlier would have included that model.

Despite missile-maker's statement, Russia's top investigative body says it regards the warplane as its top theory and claims to be protecting a Ukrainian witness who has identified the plane's pilot.

In any case, Russian President Vladimir Putin has said, Ukraine is morally responsible for the crash because it occurred in a war that Russia claims was launched by Ukraine.

LOOSE ENDS

One of the enduring mysteries of the tragedy is whether the rebels actually publicly admitted to downing the plane. Just minutes after the crash, a posting appeared on the social media account of then-rebel commander Igor Girkin, saying that the rebels had shot down a Ukrainian An-26 transport plane and it crashed in the same area as MH17. The rebels had shot down several Ukrainian planes in the early months of the war, but apparently with shoulder-fired missiles that could not reach the altitude at which MH17 was flying. The posting was later scrubbed from the account, with the explanation that the post was not by Girkin himself but by someone else with access to the account.

Girkin also was notorious for claiming that many of the people on MH17 were dead before the plane took off, which he said was based on witness accounts that the bodies were putrefying immediately after the crash.

___

Lowy reported from Washington, D.C. Mike Corder in Amsterdam contributed to this report.