The publication of a damning report into how the authorities handled child exploitation in Rotherham has prompted the leader of the local council to resign.
The independent inquiry by Professor Alexis Jay found that 1,400 youngsters suffered sexual exploitation including rape and trafficking in the South Yorkshire town over a 16-year period.
We know that the case which led to the conviction of five men in Rotherham is not the only one of its kind. Could the abuse that has already come to light be just the tip of the iceberg?
Here’s what we know (and what we don’t) about the child grooming gangs.
How many gangs?
The Child Exploitation and Online Protection Centre (Ceop) – the national anti-paedophile police command – divides networks of sex offenders into two groups.
So-called ”Type 1 offenders” target young people “on the basis of their vulnerability, rather than as a result of a specific preferential sexual interest in children”.
Ceop received intelligence from 31 out of 43 police forces on groups like this who were known or suspected to have abused vulnerable children in 2012.
FactCheck: what do we know about the grooming gangs?
There were 57 such groups, ranging from two to 25 suspects, on the radar of those 31 constabularies. We don’t know if any have now been convicted.
So-called “Type 2″ groups – where the offenders have a long-standing sexual interest in children, were much less common. Only seven known or suspected paedophile rings were reported to Ceop.
It is possible to track cases that have been through the courts via media reports, although this is pretty unscientific.
In 2011 the Times journalist Andrew Norfolk identified 17 cases that had led to convictions where there had been a similar pattern of grooming.
In all cases, the victims were vulnerable teenage girls, often in the care of social services. They were approached on the street by men, befriended and plied with alcohol or drugs, before being sexually abused.
Updating the list to include more recent convictions that fit the same pattern, we find that there have been at least 27 similar cases in the last decade.
By date of conviction, we have evidence of such exploitation taking place in Keighley (2005 and 2013), Blackpool (2006), Oldham (2007 and 2008), Blackburn (2007, 2008 and 2009), Sheffield (2008), Manchester (2008 and 2013) Skipton (2009), Rochdale (two cases in 2010, one in 2012 and another in 2013), Nelson (2010), Preston (2010) Rotherham (2010) Derby (2010), Telford (2012), Bradford (2012), Ipswich (2013), Birmingham (2013), Oxford (2013), Barking (2013) and Peterborough (2013).
This is based on a trawl of news sources so is almost certainly incomplete.
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