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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Nigel Farage warned on Friday Britain was "far less safe" and exposed to Cologne-style sex attacks because of open-door immigration.
Arthur Simpson-Kent, 48, admitted killing Ms Blake and their sons according to his lawyer.
Two brothers have been arrested on suspicion of murder after their parents were found dead in their own home over the weekend.