Alleged mistakes by police that allowed children to be systematically abused are "unacceptable", the Association of Chief Police Officers' lead on child protection said today.
But Peter Davies, who is also chief executive of the Child Exploitation and Online Protection Centre, told MPs he was not "terribly surprised" by reports that victims had reported their plight to police several times, but nothing was done.
Mr Davies was asked what happened that could have led to forces missing chances to help children in two high profile cases.
On Monday Judge Peter Hughes QC said police missed chances to bring takeaway owner Azad Miah to justice after he jailed him for 15 years at Carlisle Crown Court for a string of sexual offences against under age girls.
It followed convictions the previous week of a gang of nine Asian men at Liverpool Crown Court of plying girls as young as 13 with drink and drugs so they could "pass them around" and use them for sex.
Five girls were "shared" by Kabeer Hassan, Abdul Aziz, Abdul Rauf, Mohammed Sajid, Adil Khan, Abdul Qayyum, Mohammed Amin, Hamid Safi and a 59-year-old man who cannot be named for legal reasons.
ALSO SEE:
The 10-week trial was told that the men - who are all from Pakistan, apart from Safi who is from Afghanistan - groomed the teenage girls because they were vulnerable.
Police said one victim was forced to have sex with 20 men in one night when she was drunk.
A chance to stop the gang was missed in 2008 by the police and the Crown Prosecution Service (CPS), who apologised for their failings.
In the wake of the cases, children's charity Barnardo's said thousands of hidden victims of child sexual exploitation are still being let down by the system.
Mr Davies today told the Commons Education Select Committee he was not "terribly surprised" by allegations that victims had previously contacted police.
"If that is what happened in these cases then it is unacceptable and it is not the way the police service should respond," he said.
He said there was a "major issue nationally" - not restricted to the police service - that indicators were not picked up, but work was under way to improve the situation.
"There is a lot of work that has gone on to improve the service and of course I point out that the Rochdale case and Cumbria case and other high-profile cases do demonstrate that these are now being picked up by police forces."
Mr Davies was asked how it was possible that complaints may have been made, but nothing was done - one 12-year-old apparently complained to police three times in 2008 but no action was taken.
"Police forces are huge warehouses of information, relying on the frontline person to spot the risk factors that somebody is subjected to this kind of abuse and sexual exploitation, information which sits within police forces, sometimes goes astray, sometimes doesn't end up at the right address, and that's a common issue, not just in police forces", he said.
Giving evidence to the committee, which is carrying out an inquiry into the child protection system in England, Mr Davies urged local agencies to work together to look for signs of child sexual exploitation.
"It's very clear that unless local agencies working together actively look for signs of child sexual exploitation they not only won't spot it but might delude themselves into thinking it doesn't exist in their area.
"Our view is that it's far more prevalent than people realise."