South Yorkshire Police missed 'intelligence and investigative opportunities' to tackle child sex exploitation in Rotherham, a report has found. A host of failings left gangs  free to rape, traffic and sexually abuse at least 1,400 children  in the town between 1997 and 2013, an inquiry by the National Crime Agency (NCA) concluded. The NCA said the police force did not use 'alternative strategies' to protect victims or gather evidence, and failed to work effectively with local licencing and community safety officers. South Yorkshire Police missed 'intelligence and investigative opportunities' to tackle child sex exploitation in Rotherham, pictured, a report has found. At least 1,400 children were abused in the town over 16 years . The review was launched last December in the wake of the damning Jay report, which exposed widespread failures of the council, police and social services in tackling child sex exploitation. The controversy that followed the publication of the report led to Rotherham council leader Roger Stone leaving his post. The most high profile resignation was that of South Yorkshire's Police and Crime Commissioner Shaun Wright, who was the Rotherham councillor overseeing children's services between 2005 and 2010. The NCA review examined three current South Yorkshire Police investigations into child sex exploitation. 'Over the years, intelligence and investigative opportunities in relation to child sexual exploitation have been overlooked by South Yorkshire Police,' it stated. It added that the officers working on Operations Clover, Monroe and Mark are 'conscientious, enthusiastic and focused upon providing good outcomes'. The report acknowledged that the force had begun to make progress in protecting vulnerable children, but set out 48 recommendations of areas that need further improvement. Among them were record keeping, additional investigative opportunities, and engagement with victims. NCA director Trevor Pearce said: 'A review of these three investigations has identified improvements that need to be made at both strategic and operational level. 'Many of the issues identified by the review team have already been addressed by the force or work is in hand to do so. 'South Yorkshire Police has already made a number of arrests in relation to these matters and other offenders who believe that their past actions will never catch up with them should think again.' The NCA will now take over Operation Mark, deeming it to be 'not as developed' as the other two. Operations Monroe and Clover which will remain under police command on a day-to-day basis. Operation Mark will be integrated into the agency's Operation Stovewood, which will look at historic sex abuse cases in the South Yorkshire town. In light of its findings, the NCA will now also expand their investigation to include three further police operations, with the aim of bringing more offenders to justice. File image . In light of its findings, the NCA will now also expand their investigation to include three further police operations, with the aim of bringing more offenders to justice. Two of the investigations into child sex exploitation did not result in any cases being brought to court. South Yorkshire Police Chief Constable David Crompton has accepted the findings of the review. He said: 'The independent review of three South Yorkshire Police investigations into non-recent allegations of child sexual exploitation was something I requested as part of the NCA's investigation to ensure transparency and openness. 'The review found that the force had made a number of improvements and that staff working on the investigations were conscientious and focused and that strategic leadership was professional and appropriate. 'This highlights the significant progress the force has made in protecting vulnerable people and tackling child sexual exploitation. 'We have dedicated officers working tirelessly to support the victims and bring the offenders to justice and have made a number of arrests as part of these investigations. 'However, the NCA has made a number of recommendations for further improvements. 'We accept these recommendations and, as the NCA have recognised, the force has already addressed many of these and put steps in place to ensure other issues are dealt with in a timely manner.' Early to mid 1990s . According to the Jay Report, community workers come across examples of child sexual exploitation and find children under the care of the local authority are at risk of being targeted. 1997 . The 'Risky Business' youth project is set up to work with people between the ages of 11 and 25 in Rotherham, amid concerns young people are being abused through prostitution. Late 1990s . Youth workers start to identify vulnerable girls and young women on Rotherham's streets and refer them to children's social care. Community workers first came across examples of child sexual exploitation regarding children under the care of the local authority in Rotherham (pictured) in the mid-1990s . Early 2000s . Shaun Wright is elected as a Labour councillor on Rotherham Council. A small group of professionals from key agencies meet children at risk of, or involved in, child sexual exploitation but their work is not properly supported, according to the Jay report. Senior police and social workers think the extent of the issue is being exaggerated. 2002 . A Home Office draft report into child sexual exploitation in Rotherham criticises agencies and says there is a 'high prevalence of young women being coerced and abused through prostitution'. Police and senior officers at the council are unhappy with  the report, claiming some facts are either exaggerated or made up. The report's author does not complete her work. August 2003 . A report by strategic drugs analyst Dr Angie Heal, commissioned by South Yorkshire Police, finds there are a 'significant number of girls and some boys who are being sexually exploited' in Rotherham. In 2003, a report commissioned by South Yorkshire Police found there were a 'significant number of girls and some boys who were being sexually exploited' in Rotherham (file picture) September 2003 . The Sexual Exploitation Forum is set up, holding monthly meetings to discuss cases of children who are being sexually exploited or are at risk. April 2005 . Rotherham Council sets up a new department of children and young people’s services, with Councillor Shaun Wright appointed cabinet member for the department. April 2007 . An investigation into the grooming and sexual abuse of young boys identifies more than 70 alleged victims. A man is convicted of offences against 10 children. 2008 . Operation Central is set up to investigate men believed to be involved in child sexual exploitation. Autumn 2009 . Ofsted rates Rotherham's children's services as 'inadequate'. Councillor Wright resigns from his council cabinet post in the wake of the report. December 2009 . Shaun Wright was elected onto Rotherham council in the early 2000s and was later elected as Police and Crime Commissioner for South Yorkshire . The minister of state for young people and families serves the council with an improvement notice for its children's safeguarding services. 2010 . Five men given lengthy jail terms after they are found guilty of grooming teenage girls for sex. April 2010 . The local Safeguarding Children Board sets up a child sexual exploitation sub group. September 2012 . The Times publishes an investigation revealing that a confidential  police report had warned thousands of child sexual exploitation crimes were being committed in South Yorkshire by networks of Asian men. The newspaper also reports that agencies in the town had extensive knowledge of such crimes for decades. South Yorkshire Police refutes claims in article. October 2012 . Rotherham Borough Council, South Yorkshire Police and other agencies set up a Child Sexual Exploitation team. Home Affairs Select Committee tells force's chief constable to 'get a grip' on the issue. November 2012 . Shaun Wright wins election to become South Yorkshire Police and Crime Commissioner. He states that tackling child sexual exploitation is one of his priorities. January 2013 . The chief executive of the council, Martin Kimber, appears before the Home Affairs Select Committee to answer questions about the lack of prosecutions. August 2013 . Four women sue the council for failing to protect them when they were children. September 2013 . The council announces it is commissioning an independent inquiry. August 2014 . Professor Alexis Jay publishes commissioned report into child abuse in Rotherham, revealing more than 1,400 children had been subjected to rape, violence and trafficking  between 1997 and 2013. Rotherham Borough Council leader Roger Stone steps down with immediate effect. Mr Wright  issues a statement saying he will stay in his job as PCC, despite calls for him to stand down. Home Secretary Theresa May backs calls for Mr Wright to step down and his deputy PCC Tracey Cheetham announces she is resigning because she is 'unable to continue' in her role. In August last year, Professor Alexis Jay (pictured) published report into child abuse in Rotherham, revealing more than 1,400 children had been subjected to rape, violence and trafficking . September 2014 . Mr Wright resigns. The Labour Party suspends four of its members pending an investigation: former leader of the council Roger Stone, ex-deputy council leader, Jahangir Akhtar, Gwendoline Russell, and Shaukat Ali. November 2014 . The Independent Police Complaints Commission announces ten police officers mentioned in the Jay Report are under investigation . December 2014 . National Crime Agency (NCA) begins investigation into child sexual exploitation in Rotherham . February 2015 . Devastating report is published by Louise Casey. Communities Secretary Eric Pickles announces new elections in 2016 to replace Rotherham Council's 'wholly dysfunctional' political leadership.
National Crime Agency examined police investigations into child sex abuse . Concluded police failings left gangs free to prey on children in Rotherham . NCA will review three more operations in hope of finding more offenders .