White House adviser Tony Blinken says there is evidence that Russia is preparing to deliver more powerful rocket launchers to separatist rebels in eastern Ukraine.
Western powers have accused pro-Russian rebels in the area of shooting down Malaysia Airlines flight MH17 with a rocket.
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ITV News witnesses the devastating aftermath as 600 people remain missing and 300 are confirmed dead.
Wayne Lotter, the co-founder and president of the conservation organisation PAMS Foundation, has been shot dead by gunmen in Tanzania.