Councillor Ken Wyatt says he knew grooming was taking place but was told discussing it could disrupt police inquiries

Councillors in Rotherham were told at a seminar in 2005 not to publicly discuss information about the town's child sexual exploitation problem because it was "confidential" and could jeopardise police investigations, according to three councillors present at the time.

Prof Alexis Jay's report on the 1,400 children failed by the council and agencies said that such "explicit content" about the issue was given to 30 councillors at the seminar that "few members or senior officers could say 'we didn't know'."

On Wednesday, one councillor, Ken Wyatt, was asked by a member of the public at an emotional council meeting why he and colleagues did not act following the seminar.

Wyatt acknowledged that he knew then that grooming was happening, both locally and nationally, and councillors were told that "steps were being taken to deal with it". But he insisted: "It was not at the scale we have subsequently found out."

He said "we were told to treat it as very confidential" and that talking about it publicly "could disrupt inquiries" then being made by the police.

He added: "We were told it was an incredibly difficult area to work in, incredibly difficult to get convictions."

His response did not go down well with his questioner, who said: "Our children were at risk. Our children were being raped. Our children were being abused. And you are telling me as a borough councillor, bare-faced telling me that you weren't allowed to say anything?"

Sue Ellis, another Labour councillor present at the 2005 seminar, said she too had been told not to talk out about what she had learned during the session. "We were asked for it to be restricted … so that we didn't jeopardise police prosecutions. I think it would be a very brave person who would have gone out and actually jeopardised police prosecutions as people have criticised them for not getting these," she said.

Joyce Thacker, strategic director of children's services at the council, was asked by a Ukip councillor how Rotherham children's services had won an award while all the abuse was going on unchecked. In 2007, the Local Government Chronicle award for management of children's services went to Rotherham. "Were these people total idiots who did the appraisal?" asked the councillor, John Turner, or was information about the town's grooming problem "suppressed"?

Thacker said: "I can't recall the criteria for the award."

Turner was at the 2005 seminar while he was a Conservative councillor, before defecting to Ukip. Jay's report says that in 2006 he requested a meeting with the then council leader, Roger Stone, in which "he expressed his concerns about CSE … He told the inquiry that the council leader advised him the matters were being dealt with by the police and requested that he did not raise them publicly."

The deputy council leader, Paul Lakin, apologised again for what happened in the town at the beginning of a packed meeting of the council's ruling Labour cabinet.

He said: "We have all been appalled by the terrible contents of this report.

"It is with a deep sense of regret that we are here today to discuss how, in the past, as a council, we badly let down young people and families we were here to protect."

At a separate meeting on Wednesday, Sheffield council unanimously passed a vote of no confidence in Shaun Wright, South Yorkshire's police and crime commissioner. Wright, who was Rotherham council's cabinet member for children and young people from 2005-2010, has ignored calls from the Labour party, the prime minister and numerous MPs to step down.

Martin Kimber, Rotherham's chief executive, said the council had gone through a list of all current employees who were criticised by any of Jay's interviewees. As a result, two individuals had been asked "further relevant questions as to their knowledge of child sexual exploitation", he told the meeting.

The council had no power to question former employees, he added.

The public questions were continually interrupted by shouts from the galleries and interjections from Ukip councillors in the chamber.

Calls for the councillors to resign were greeted with applause.

Outside the Rotherham council meeting, a 17-year-old girl, who said she was sexually exploited in the town when she was as young as 12, protested along with her mother. The teenager said: "Foster carers used to drop me off to meet a specific man who was 23 years old when he started doing that to me. Police raided where I was staying with him because I was missing to the local authority but they arrested me and not him. "It wasn't clear to them that he'd been abusing me even though I was stood there naked. That wasn't clear enough to them. He was already on the sex offenders register."

The girl said none of the men who abused her have ever been arrested or prosecuted.

Last week's report by Jay outlined details of exploitation over a 16-year period with examples of girls who were raped, trafficked, threatened with extreme violence and ignored by the statutory authorities.

The Jay report sparked a wave of criticism of police, councillors and local authority officials but only the council leader, Stone, has resigned in its wake.

The home secretary, Theresa May, told MPs on Tuesday that the communities secretary, Eric Pickles, was "minded" to commission an independent investigation into Rotherham borough council following concerns of "inadequate scrutiny by councillors, institutionalised political correctness and covering up of information and the failure to take action against gross misconduct".

The council was under Labour control throughout the period in question, and the party has now suspended the authority's former leader, Stone, and ex-deputy leader, Jahangir Akhtar, as well as serving councillors Gwendoline Ann Russell, who chairs the town's looked-after children scrutiny panel, and Shaukat Ali, a former mayor.

A report prepared for the meeting on Wednesday by the council chief executive, Martin Kimber, said: "The [Jay] report is critical of past actions in a number of areas, but at the core is poor political and managerial leadership.

"The report indicates: 'By 2005 it is hard to believe that any senior officers or members, from the leader and chief executive downwards, were not aware of the issue.'

"It is clear from the report that at this time some senior officers responsible for safeguarding simply did not do their jobs effectively."

The South Yorkshire chief constable, David Crompton, revealed on Tuesday that 12 new victims of child sexual exploitation in Rotherham had come forward since the publication of last week's report.

Crompton told the House of Commons home affairs committee that he had 62 officers dedicated to dealing with child sex abuse, compared with just three in 2010 and eight in 2012.

His comments came after he announced an independent inquiry by an external police force into South Yorkshire police's handling of sex abuse complaints over many years.

The committee chairman, Keith Vaz, told members that South Yorkshire's embattled police and crime commissioner (PCC), Shaun Wright, had agreed to give evidence.

Wright was a Rotherham councillor for more than a decade before his election as PCC and, between 2005 and 2010, he was the cabinet member responsible for children's services.

He has resisted top-level calls for his resignation, including from the prime minister, David Cameron, May and the Labour leader, Ed Miliband.

Wright will face a no-confidence vote on Wednesday afternoon at a meeting of Labour-run Sheffield city council – the largest local authority in South Yorkshire.

The vote was proposed by Sheffield Lib Dems.

Colin Ross, leader of the Lib Dem Group, said on Tuesday: "Sheffield city council needs to show that it takes its responsibility to protect vulnerable young people extremely seriously. While Shaun Wright remains in post, local people cannot have confidence in the police to carry out this role.

"If this vote goes through tomorrow, I do not see how Shaun Wright can remain in post. His position will be untenable."