BBC News' sports news correspondent Dan Roan has tweeted:
BREAKING FA Chairman apologises: "We are deeply sorry this tragedy occurred at a stadium the FA selected...I offer a full apology.."
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The report also said that many graduates do not even see a 'earnings premium' from their years at university.
The country's counter-terrorism forces have regained control of the facility.
The commissioner of the Metropolitan Police has said he cannot promise the public an attack will not take place.