In his statement outside Downing Street, David Cameron said:
"What happened yesterday in Woolwich has sickened us all. On our televisions last night and in our newspapers this morning we have all seen images that are deeply shocking.
"The people who did this were trying to divide us. They should know something like this will only bring us together and make us stronger."
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One of the great tragedies of the First World War is the number of youths who lied about their age to enlist particularly in the Royal Navy.