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By Matt Siegel
SYDNEY, July 23 Australian Prime Minister Tony Abbott said on Wednesday that it was still unclear how many bodies from downed Malaysia Airlines Flight MH17 had arrived in the Ukrainian city of Kharkiv and how many may have been left behind at the crash site.
Five refrigerated wagons containing 200 body bags reached Kharkiv on Tuesday after pro-Russian separatists agreed to hand over the plane's black boxes to Malaysian authorities and the bodies to the Netherlands, where many victims had lived.
The black boxes arrived in Britain on Wednesday.
Abbott said that based on an initial inspection of the remains in the train carriages, that it was unclear how many bodies may still be left behind in rebel-held territory.
"Based on early inspection of the trains in Kharkiv, we just don't know how many bodies we have," Abbott told reporters.
"It's quite possible that many bodies are still out there in the open, in the European summer, subject to interference and subject to the ravages of heat and animals. That is the predicament in which we find ourselves."
The Boeing 777 was shot down last week in eastern Ukraine en route from Amsterdam to Kuala Lumpur, killing all 298 passengers and crew on board. Twenty eight Australians were killed. (Reporting by Matt Siegel; Editing by Nick Macfie)