Lieutenant Commander Brian Badura from Isaf says they are trying to work out just what happened when two British soldiers were killed by one of their Afghan colleagues.
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Colo became a mother of three, grandmother of 16, great-grandmother of 12 and great-great-grandmother of three.
The district's director of homeland security has said officials are planning for 800,000 to 900,000 people to attend the ceremony.
The Supreme Court is set to decide on whether disabled travellers are legally entitled to have priority use of wheelchair spaces on buses.