Secretary-General Ban Ki-moon's office issued a statement Thursday expressing "grave concern" about the incident, but said U.N. officials lacked details about exactly what had happened.

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He called the incident a "matter of grave concern to the United Nations, " adding that the safety and welfare of civilians must be a top priority in the planning of any military operation.

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In the letter, the foreign secretary makes its clear that the UK has made no decision about the future of the arms embargo but restates the government's view that it may need to be amended, or even lifted, in the event of a "grave deterioration" in conditions or a specific incident.

BBC: UK Politics

He identified only one incident which coincided with Mr Moloney's book Voices From The Grave, based on interviews with other ex-paramilitaries for the same project.

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