Dai Davies, the former head of royal protection for the Metropolitan Police, says accidents like these are embarrassing for the service, but that training for officers is very rigorous.
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A cloudy night with some patchy rain possible in places, clearer spells possible in the northeast. Milder than of late.
You've been sending us pictures of your children dressed up for World Book Day.
A brother is facing jail for killing his step-sister when she fell off a motorbike he was 'racing' in his car in December 2013.