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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Traffic on the M4 from Coryton to Cardiff is at a standstill following a multiple vehicle crash.
The ex-footballer, who lives in Flintshire, said he thought he was clever sheltering his car from the snow.
Police say the body of a Cardiff man who went missing in February 2015 has been found in Forest Fawr, Castle Coch.