Detective Chief Inspector Harry Hennigan has defended the decision by authorities to let a man out on day release from prison, who subsequently carried out a series of armed raids.
Sean Bradish was handed down two life sentences having already received one previously.
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It is the fourth time in five years that the London borough has topped the rankings, according to data from the ONS.
Catherine Burke's body was discovered at a house in a quiet street in Muswell Hill last Thursday evening.
Residents said living next to the 40 foot high stinking mound was a 'living nightmare'.