(BBC News) The United Nations has raised grave concerns about reports of high civilian casualties in the Iraqi city of Mosul.

A senior UN official in Iraq said she was stunned by accounts of “terrible loss of life”, after claims that at least 200 people had been killed in an air strike by the US-led coalition.

US warplanes are supporting the Iraqi Army’s mission to retake Mosul from the Islamic State (IS).

US media reports say an investigation is under way.

It is not known exactly when the deaths are alleged to have happened.

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