The Inspector of Constabulary report issued Friday finds police to have mishandled roughly three-quarters of the 374 cases it reviewed.
Chief inspector Matt Parr said the inspectors found "serious errors of judgment, inconsistency, unacceptable delays and a lack of leadership which meant that children are not being protected properly."
He said in many cases victims of sexual abuse were not protected, evidence was misplaced and offenders left in a position to pose an ongoing risk to children.
London Mayor Sadiq Khan called the report "deeply troubling."
An earlier report had found many errors in the police department`s handling of a pedophile ring.
Inspector finds London police failing on child abuse cases
25 November 2016
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An inspector`s report has found that London`s Metropolitan Police are putting children at risk because of poor handling of child sex abuse cases.
