A six-month study by the Child Exploitation and Online Protection Centre (Ceop) found that cases came to light where agencies worked together to identify the issue, but in many areas this is not happening.
Ceop received a limited response from agencies, especially children’s services and local safeguarding children boards (LSCBs), with only 13 LSCBs responding to the request for information.
The highest response was from police forces, although a significant number of forces reported that they didn't hold any relevant data.
From the information provided, Ceop found that between March 2008 and January 2011 there were 2,379 individuals reported as being possible offenders in relation to street grooming and child sexual exploitation. A total of 2,083 victims of child sexual exploitation were reported for the same period, although true figures are thought to be far higher.
"Where police, children’s services and voluntary sector agencies have worked together, co-ordinated by LSCBs, to identify and address child sexual exploitation, a significant number of cases have come to light," the report states.
"However, very few cases are known in areas where agencies do not routinely engage victims and collect data. Agencies that do not proactively look for child sexual exploitation will fail to identify it. As a result, the majority of incidents of child sexual exploitation in the UK are unrecognised and unknown."
Of cases where enough information was available for analysis, ages of offenders were disproportionately skewed towards young adults within the 18 to 24 age range.
The ethnicity of 38 per cent of the offenders was unknown, 30 per cent were white, 28 per cent Asian, three per cent black and 0.16 per cent Chinese, although Ceop has warned against drawing firm conclusions from these figures without further research.
The report found that despite all LSCBs having responsibility for co-ordinating the protection of children from sexual exploitation agencies working together, a comparatively small number were effective at it.
"In this complex crime you cannot tackle it or support victims unless you can see this crime, and in order to see it agencies need to look for it," said Ceop chief executive Peter Davies.
"What we found from talking to academia, frontline police officers and the wider safeguarding community was that often understanding and awareness among agencies of this complex crime was not widespread enough.
"It was not being approached with sufficient appreciation of the victim's perspective and we are still some way from creating environments where the victim is encouraged and supported in coming forward.
"It is only by proactively looking for child exploitation that agencies are able to identify and support victims and this requires a long-term and co-ordinated approach."
Barnardo’s chief executive Anne Marie Carrie said the report, called Out Of Mind, Out Of Sight, confirms previous suspicions that only some victims of sexual exploitation are coming forward to ask for support.
"Still more children remain trapped under the control of their abusers because we are failing to spot the signs – such as going missing from home," she said.
"If we are serious about protecting vulnerable children and bringing perpetrators to justice for their crimes, then agencies must work together to make the connections and gather the evidence that will lead to prosecutions."
The Children’s Society’s policy director Enver Solomon said: "For far too long child grooming has been a hidden issue, with dangerous perpetrators targeting vulnerable girls and boys in the shadows of our society.
"The Ceop assessment exposes the significant challenges faced in stamping out this shocking abuse. Critically, it highlights that children who run away are particularly vulnerable to exploitation yet professionals are often unaware of this.
"Child grooming cannot be addressed without actively looking at the issue of children running away.
"It is essential that local authorities and the police join the dots so that every time a child runs away it triggers a response that protects them from any potential abuse. Unless and until there is an improved response, too many children will continue to be victims of horrific exploitation."
