Media playback is unsupported on your device Media caption Ann Lucas: "The police were just very blinkered on what their targets were"

Hundreds of young people at risk of child sexual exploitation in Sheffield were let down by police, a whistleblower has claimed.

Ann Lucas, who ran the city's sexual exploitation service, told BBC News she had regularly passed details about alleged abusers to senior officers.

They had repeatedly failed to act, she said, adding the force's priorities had been "burglary and car crime".

South Yorkshire Police said the allegations would be investigated.

The force is already facing an investigation following the publication of an independent report in August that accused it of failing child-exploitation victims in Rotherham.

That report found at least 1,400 children had been abused over a 16-year period.

'Exploitation gangs'

However, Sheffield, just six miles from Rotherham, was seen as a model for tackling child sexual exploitation.

In 1997, the council set up a unit to look at the problems of young girls engaged in prostitution in the city.

The aim was to understand what drove them to it and to treat them as victims, not criminals.

In 2001, the city secured Home Office funding to set up the Sexual Exploitation Service, bringing together council, voluntary and health services.

The police were also involved, initially providing a constable to work with the team on a part-time basis.

In later years, the police provided some funding to the service and increased the commitment of the part-time officer.

I felt for years that I was banging my head against a brick wall because it wasn't a priority Ann Lucas, Whistleblower

Between 2001 and 2013, at least 668 young people, mainly girls, were referred to service, according to figures obtained by BBC News.

Some were as young as 11, most were white, 14 to 15 years old, and living at home.

About a third were under the care of the council.

Ann Lucas ran the project from its inception in 1997 until she retired in 2012. She is full of praise for the front-line officers she worked with, but is highly critical of some of their superiors.

In 2003-04, she and her team started mapping by whom the children were allegedly being abused, the addresses of where they were being exploited, the names and nicknames of the perpetrators and their car registration details.

'Misconduct?'

She said all the information had been passed on to senior police officers but that no prosecutions had followed.

She said: "There were arrests and child abduction notices [were served], so they might move off that young person, but without the prosecuting strand being strong, we could divert the person away but with the message [to the abusers] that you could get away with this, so they would move on to other young people."

In 2006, the service became aware that a group of teenage girls were being abused, allegedly by a group of Iraqi Kurdish men.

A document seen by BBC News shows that one 13-year-old girl told officials she had been raped by five men, had experienced physical violence, including being punched, kicked and burned with cigarettes, and had had threats made against her family if she told anyone.

Ms Lucas said she and another council official, had gone to see Jon House, who was chief superintendent for Sheffield at the time.

She said she had showed the former chief superintendent all the information they had collected, and asked that a police investigation be launched into the allegations.

She said: "I was told that their [the force's] priorities were burglary and car crime and we had to cope with no extra police resources. It was extraordinary. How could anyone in their right mind think that burglary and car crime is more important than young people being raped?"

Staffing boost

Mr House, who has left the police and is now a senior manager with PWC consultants, said: "Without more, I cannot immediately remember the details of a meeting alleged to have taken place eight years ago. Throughout my period we had to deal with very serious issues on a daily basis."

South Yorkshire Police said: "This is a question that only those involved can answer. South Yorkshire Police will look into these allegations and where there is evidence of any misconduct referrals will be made to the IPCC."

Ann Lucas took her information, which included allegations that the girls were being moved to other cities, to the newly opened Human Trafficking Centre. They assessed it and asked South Yorkshire Police to investigate the claims. "They re-branded it as trafficking, which was a priority," said Ann Lucas.

"They took exactly the same information back to South Yorkshire Police a few months later who took it on and mounted an investigation."

Operation Glover led to six men being convicted. Aziz Hamed and Ajad Mahmoud were each sent to prison for 10 years for serious sexual offences, while two others also received substantial custodial sentences.

South Yorkshire Police said Operation Glover "was focused on child sexual exploitation and not human trafficking, although we understand the two are often intrinsically linked".

Ms Lucas is delighted that more officers are now being asked to investigate child sexual exploitation and that it's finally, maybe, receiving the priority it deserves. "I felt for years that I was banging my head against a brick wall because it wasn't a priority," she said.

Ms Lucas passed all her allegations on to Chief Constable David Crompton, of South Yorkshire Police, during a meeting last month.

In a statement, the force said "they will look into the allegations and where there is evidence of any misconduct referrals will be made to the Independent Police Complaints Commission".

They added since 2013, there had been a six-fold increase in staff dedicated to tackling child sexual exploitation.

And they said the National Crime Agency was to investigate historical allegations of sexual grooming and that the terms of reference for that inquiry were being finalised at the moment.