Grassley, meanwhile, is demanding that the White House counsel make public details of her internal inquiry in addition to an independent investigation of White House staffers.

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Grassley is demanding that, in addition to an independent investigation of White House staffers, the White House counsel make public details of her internal inquiry.

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"We are working closely with the Turkish national police to make a full assessment of the damage and the casualties, and to begin an investigation, " she said.

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The crash caused an intense fire that incinerated much of the plane, something that will make the investigation difficult, Duprie said.

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In his plea for an investigation, Karrubi says he has heard descriptions of torture and violence that make his "body shake, " though he doesn't specify a prison.

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