Kiev: Nearly four months after Malaysia Airlines flight MH17 was shot down in eastern Ukraine, killing 298 people, the disaster remains highly controversial as the Netherlands on Monday holds a memorial ceremony for the dead.
The Malaysia Airlines Boeing 777 disappeared from radar screens at 1320 GMT on July 17 over territory controlled by pro-Russian separatists in eastern Ukraine.
Flight MH17 had taken off just after 1000 GMT from Amsterdam`s Schiphol airport and was heading for Kuala Lumpur.
It was carrying 298 passengers and crew, of which 193 were Dutch and 38 Australian citizens or residents.
The fragments of the plane fell to earth near the village of Grabove in the rebel-held zone.
Ukraine and the West claim that separatist fighters had downed the plane with a BUK surface-to-missile supplied by Russia.
US President Barack Obama stressed that the missile was fired from territory controlled by Russian separatists while Secretary of State John Kerry outlined "extraordinary circumstantial evidence" that rebels were behind the disaster.
The West imposed tougher sanctions on Russia following the disaster, in a sign of its anger.
Messages posted on, and quickly removed from, rebel websites and conversations purportedly intercepted by Ukrainian security forces just after the crash suggested that the missile could have been fired in error by separatists who mistook the airliner for a Ukrainian military plane.
On Sunday, British citizen journalism site Bellingcat published an investigation based on photos, videos and documents posted online claiming that a BUK launcher seen in the rebel-controlled zone on July 17 was part of a convoy travelling from the Russian 53rd Anti-Aircraft Missile Brigade in Kursk to near the Ukrainian border as part of a training exercise from the end of June. The same launcher was later filmed minus one missile.
The rebels deny having shot down the plane. Russia`s government denies having supplied them with missiles and accuses Kiev of falsifying information. The defence ministry has suggested that Ukraine`s army could be behind the downing, saying that a Ukrainian fighter jet was in the vicinity and that surface-to-air missiles operated by Ukrainian forces were in position in the zone.
In an initial report published on September 9, the Dutch Safety Board, which is investigating the crash, said the plane had been hit by numerous "high-energy objects".
Malaysian Prime Minister Najib Razak said the report prompted "strong suspicion that a surface-to-air missile brought MH17 down" and called for further investigations but Dutch Prime Minister Mark Rutte said the case was still "wide open".
The report did not apportion blame and inspectors were not able to access the crash site due to security issues, instead relying on information from black boxes, Ukrainian officials and pictures and video.
Investigators say they need to conduct further investigations before publication of their final report, expected in summer 2015.