The key to preventing child sexual exploitation is stopping young people who are "determined to put themselves at risk", from running away from care homes, the chief constable of Greater Manchester Police said.
Sir Peter Fahy insisted that the police had learned lessons after an investigation highlighted "significant failures" in the handling of widespread abuse in Rochdale.
The chief constable rejected calls from ex-detective Margaret Oliver for a full independent inquiry into the force's actions.
"The issue is that we still haven't solved the key issue behind CSE (child sexual exploitation) which is: how do you protect vulnerable young people who are determined unfortunately to put themselves at risk, that don't understand the degree to which they are making themselves vulnerable," he told BBC Radio 4's Today.
Asked if he saw the problem as being children putting themselves at risk, he went on: "Yes absolutely. Because of their upbringing, because of their difficult situation and because they are in care, every single day we have large numbers running away.
Police have admitted they failed to respond adequately to child sexual exploitation in Rochdale.
IPCC Commissioner James Dipple-Johnstone said:
There was a failure to recognise the seriousness and scale of what was happening in Rochdale.
It is appalling that young girls were being exploited and abused and the police did not handle it properly.
Greater Manchester Police has admitted that the focus in Rochdale was on tackling volume crime such as robbery and burglary.
The force simply did not recognise how to respond to child sexual exploitation on this scale.
An ex-detective said a report on police failures in the Rochdale child sex abuse scandal gave no new insights and that children in the area were still at risk.
Margaret Oliver said: "I know of men who have never been arrested, who are still walking the streets of Rochdale, who victims have named and accused of abusing them."
Oliver called for a full independent investigation of the kind carried out into similar problems in Rotherham.
"Virtually everything that is in that report today we were very well aware of in December 2010. The question that begs to be asked is why it has taken seven years to report that when that was widely known five years ago by all the officers working on Operation Span," she told the BBC Radio 4 Today programme.
"This was an opportunity, which has been missed again, to bring it all this out into the open. It is a nationwide problem and there is still an overwhelming desire to conceal the truth."
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Ten men have been charged as part of an ongoing investigation into child sexual exploitation in Rochdale.
The men, nine of whom are Asian, are accused of a catalogue of serious sex offences against seven victims, aged as young as 13 at the time of the alleged offences, between 2005 and 2013.
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Three suspected slave masters have been arrested after 20 people were rescued in a raid at a factory.
The people were working 80-hour weeks for just £25, producing pictures and frames for a number of major high street companies, police said.
Three men aged 51, 43 and 40 were arrested on suspicion of a forced labour conspiracy and of human trafficking after the factory in Rochdale, Greater Manchester, was raided.
Officers said the workers - who also complained of being physically attacked by their employers - were paid £125 each for their week's work, but were then forced to hand back £100 for rent and travel, leaving them barely any money to survive.
A 24-year-old man was also arrested on suspicion of immigration offences.
Seven people have been arrested in Greater Manchester as part of a probe into child sexual exploitation.
Six men and a teenage boy are being questioned on suspicion of conspiracy to commit sexual acts with a child.
The arrests took place following raids in the Rochdale and Oldham areas.
Police said the suspects, aged between 16 and 47, were of mixed ethnicity.
Detective Chief Inspector Andy Aston said: "The team were initially looking at reasons why two girls, aged 15 and 13, and a 13-year-old boy were going missing from home.
"Officers spoke to one of the girls who suggested they were being groomed between 16 September and 17 October 2014.
"A swift investigation was launched and agencies worked together which has resulted in these arrests across the Rochdale and Oldham areas plus the safeguarding of three vulnerable children."
The long awaited report into child sexual exploitation in Rochdale has been criticised by a health worker who helped to expose the scandal.
Sara Rowbotham has called for a full national inquiry into child grooming as she says the report, by MP Ann Coffey, doesn't go far enough in holding police and social services to account.