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Terror threat ahead of 9/11 anniversary

The US secretary of state has warned that al-Qaeda is behind a credible threat to Americans in the run-up to the anniversary of 9/11.

Hillary Clinton said there had been a "specific, credible but unconfirmed report" of an attempt to target New York and Washington DC.

President Barack Obama is to visit New York and Washington on Sunday as the US marks 10 years since al-Qaeda attacked.

Steve Kingstone reports.

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