Estimate, a racehorse owned by the Queen and trained by Sir Michael Stoute, has tested positive for morphine, a prohibited substance, Buckingham Palace announced.
Initial indications are that the positive test resulted from the consumption of a contaminated feed product, the palace said.
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Some of the children at the Royal Free Hospital in London were less than impressed with their visit from Alex Oxlade-Chamberlain.
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The FBI said three key elements of the Sony Pictures cyber attack led them to identify the administration in Pyongyang as the culprits.