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International experts pushed today with their painstaking probe at the vast crash site of downed flight MH17 in eastern Ukraine, deploying sniffer dogs to help find any remains still left at the scene.
Some 70 Dutch and Australian police investigators were back for a second day to scour through the wreckage, while those leading the hunt have warned the grim task could take some three weeks to complete.
An AFP journalist, asked by the probe team to remain a few hundred metres from the investigators, saw search crews fanning out across a field and occasionally bending down to collect and bag objects.
A refrigerated ambulance van was on site to store any remains found, while armed rebel fighters kept an eye on the gathered journalists.
The shooting down of the Malaysia Airlines plane more than two weeks ago, killing all 298 people on board, refocused world attention on the conflict in Ukraine and pushed the United States and European Union into imposing the toughest sanctions against Moscow since the Cold War.
Washington accuses insurgents of blowing the airliner out of the sky with a surface-to-air missile likely supplied by Russia, while Moscow and the rebels have pointed the finger at the Ukrainian military.
In a telephone call with Russian leader Vladimir Putin on Friday, US President Barack Obama expressed his "deep concerns" about Moscow's increased support for separatists rebels waging a brutal conflict against Kiev that has claimed more than 1,150 lives since mid-April.
"Right now what we've done is impose sufficient costs on Russia that, objectively speaking... President Putin should want to resolve this diplomatically, to get these sanctions lifted, get their economy growing again, and have good relations with Ukraine," Obama told an impromptu news conference.
"But sometimes people don't always act rationally," he added.
The Kremlin said the two leaders had agreed that the standoff in Ukraine -- where pro-Russian rebels are battling government forces -- was "not in the interest of either country".
But Putin lashed out at the latest economic sanctions as "counterproductive, causing serious damage to bilateral cooperation and international stability overall," the Kremlin said.
