Derbyshire Chief Constable Mick Creedon's report also revealed that the practice could have been more widely used, beyond Scotland Yard's Special Demonstration Squad (SDS) and the National Public Order Intelligence Unit (NPOIU), by police officers and possibly the security services.
It said: "It is a fact that undercover officers working in the field of serious and organised crime also need to establish secure covert identities, create legends, obtain documentation and if necessary withstand invasive scrutiny by their targets.
"It would be a mistake to assume that the identities of dead children were used solely by the SDS and the NPOIU and the possibility is that the tactic was more widely used."
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