Daybreak's Lucy Watson speaks to Debra Accomondo - who knew one of the victims of the US shooting.
She told Daybreak: "It's one of those defining moments where you know your world is going to change."
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The study, conducted by the European Banking Authority, looked at how much capital would be used up in adverse economic conditions.
The victims were playing the popular game in Whittington Park in Holloway on Tuesday night, when three males suspects approached them.
A former Royal Marine who was recently engaged has been killed in a climbing accident in the French Alps.