The Rotherham child sex abuse report has revealed that out of six investigations into sex offences against children between 2007 and 2013, only one resulted in prosecution and subsequent conviction.

Around 1,400 children were subjected to "appalling" abuse in the South Yorkshire town over a 16-year-period between 1997 and 2013, the report has found.

The inquiry, carried out by Professor Alexis Jay, a former chief inspector of social work in Scotland, said there had been a "collective failure" by both South Yorkshire police and the local council to stop the abuse.

The majority of the victims identified in the report were girls, some as young as 11 years old. In more than a third of these cases, the victims were known to child protection agencies.

Failure to convict

Between 2007 and 2013, the South Yorkshire police undertook a series of operations to investigate cases of suspected child sexual exploitation. Yet only the first inquiry led to convictions.

In 2008, Operation Central investigated groups of men believed to be involved in the abuse of children. It ended in 2010 with five convictions.

Both Operation Czar and Operation Chard, which commenced in 2009 and 2011 respectively, led to the issuing of abduction notices - legal notices instructing adults to cease contact with specified children. However neither investigation yielded a conviction.

In the summer of 2012, Operations K-Alphabet and Kappa began. These were joint investigations run by the South Yorkshire police along with children's services. And later that year, Operation Carrington investigated the risks posed to young people in Rotherham. None of these operations led to convictions.

In 2013, a final police operation into historic cases of organised sex abuse in Rotherham was announced.

Children witnessed 'brutally violent rapes'

Jay's independent inquiry, which examined how Rotherham's social services dealt with allegations of child sex abuse between 1997 and 2013, found girls as young as 11 were gang-raped and taken to other towns and cities in the north of England to be abused, beaten, and doused in petrol.

"They were raped by multiple perpetrators, trafficked to other towns and cities in the north of England, abducted, beaten and intimidated," she said in a summary of her findings.

"There were examples of children who had been doused in petrol and threatened with being set alight, threatened with guns, made witness to brutally violent rapes and threatened they would be next if they told anyone."

Roger Stone, the leader of Rotherham's Labour council, announced his resignation shortly after the details of the report were announced.

"Having considered the report, I believe it is only right that I, as leader, take responsibility on behalf of the council for the historic failings that are described so clearly in the report and it is my intention to do so," he said.

"For this reason, I have today agreed with my Labour group colleagues that I will be stepping down as leader with immediate effect."

Stone was appointed leader of the council in 2003, and had served in the council for more than 25 years. In 2009 he was awarded an OBE "in recognition for his services to local government".