She later checked his school medication card and saw that in the weeks prior, he'd missed nearly half his regular doses of medication because office staff hadn't called him in to take it.

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The former embassy official said most staff in the embassy don't believe the Foreign Office explanation because in recent weeks al-Ayoubi had actually been trying to dismiss staff members whom he suspected of supporting the opposition.

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In the letter, Foreign Affairs Committee Chairman Richard Ottaway asked why rumors concerning suspicions about Mr. Heywood's death which Mr. Hague had said reached the foreign office staff in mid-January weren't communicated to ministers immediately.

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Staff members at Mr. DeMint's office weren't available for comment.

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