One of the biggest victims' groups involved in the Independent Inquiry into Child Sexual Abuse has announced it is formally pulling out of the probe.
In the latest setback for the inquiry, set up by then home secretary Theresa May, the Shirley Oaks Survivors Association, described it as a "stage-managed event which has now been contrived in such a way that it enables the guilty to wash their dirty hands, whilst the establishment pats itself on the back".
The group, which represents people affected by abuse at children's homes run by Lambeth council in south London, said in a statement: "Having watched the IICSA unpalatable circus stumble and lurch from crisis to crisis with multiple resignations and claims of racial and sexual abuse thrown into the mix, it no longer matters whether we think the inquiry is just another stitch-up because it's clearly a botch job that needs a drastic overhaul if it is ever to achieve its initial objectives."
The announcement comes two days after it emerged that another senior lawyer at the inquiry had resigned.
Aileen McColgan, a law professor at Kings' College London involved in the inquiry's investigations into the Anglican and Catholic Church, reportedly quit due to concerns over the inquiry's leadership.
Her departure follows the resignation of the inquiry's senior counsel, Ben Emmerson, and his junior colleague, Elizabeth Prochaska.
The inquiry has also had four different chairwomen since it was set up in 2014.
In its lengthy and highly critical statement, the association called on panel members to resign "for the sake of all those children who were abused historically", saying survivors were being re-traumatised by the perceived failings.
The group said it feared current chairwoman Professor Alexis Jay is "an uninspiring leader" and it does not believe she is the right person to uncover the truth behind allegations of historical abuse, expressing disappointment at not having met her since she was appointed in August.
In a scathing conclusion, the association said the inquiry is an "opportunity lost" which "will leave a pigment of shame on the Government's hands".
The scale of the sweeping probe has increasingly come under the spotlight. Described as the most ambitious public inquiry ever launched in England and Wales, it is running a string of investigative strands spanning several decades.
It was initially earmarked to last for five years but there have been suggestions it could run for as long as a decade.
Following her resignation, former chairwoman Dame Lowell Goddard said there was an "inherent problem" in the inquiry's "sheer scale and size".
The inquiry spent £14.7 million out of a £17.9 million budget in 2015/16.
Prof Jay has spoken of her hopes for the inquiry to complete most of its work by 2020.
Earlier this week the inquiry announced it was delaying the strand of its investigation which is focusing on the handling of the case of late peer Lord Janner.
A spokeswoman said this was "in order to allow the ongoing police and IPCC investigations to continue so that we can avoid potential issues around witness overlap".
Lord Janner, 87, who died in December, is alleged to have abused youngsters over a period spanning more than 30 years dating back to the 1950s, with offending said to have taken place at children's homes and hotels.
The allegations against him, which are denied by his family, were due to be examined at hearings of the public inquiry.
Raymond Stevenson, chairman of the Shirley Oaks Survivors Association, said members voted on Saturday that they no longer wanted to be part of the inquiry.
Mr Stevenson said that Sosa had co-operated with a previous inquiry involving the Metropolitan Police and Lambeth Council which identified 50 potential suspects, but led to only three arrests. Sosa is now preparing to publish its own report naming 60 people as paedophiles.
"In the last inquiry, some of our members committed suicide, and people need to take that on board," Mr Stevenson told the BBC Radio 4 Today programme.
"They went through a five-year inquiry and they committed suicide. So if you are asking do we feel safe and comfortable to put our members through an inquiry that is openly failing - failing tragically, failing publicly - it's not acceptable for us to put them through this.
"The inquiry needs to sort itself out. They need to get rid of Alexis Jay, who's been parachuted in by the Home Office. She's not the right person."
Mr Stevenson said he did not believe that Sosa members would be to blame if the child sex inquiry collapses, telling Today: "The responsibility lies with those people who put the inquiry together. We don't accept any responsibility for us having to pull out."
He added: "They can do it without us. If they want to do a tick-box exercise, they can sit at their computers and go through the figures. We were persuaded to take part in this because we believed we were going to get justice and to expose what took place in Lambeth. If it's going to be the inquiry which we believe it's going to be, then they don't need us.
"We're going to carry on doing our investigation, we're going to publish our interim report which identifies 60 paedophiles."
Labour MP Chuka Umunna, a member of the House of Commons Home Affairs Committee, said he did not have confidence in Prof Jay as chair of the inquiry and wanted to see a judge of High Court level or above appointed in her place.
Mr Umunna - who stressed that he was not speaking on behalf of the committee - said: "The concern here is whether you've got a chair that can command the confidence of the majority of survivors and whether they are up to doing the job.
"Can Prof Jay bring the heft and forensic capacity of a judge to this inquiry, which is what is needed? I'm not confident that she can.
"There's an ongoing issue about the fact that she's come from three decades in social work. For many of the survivors that is a problem because a lot of the perpetrators came from that profession. You can't just sweep that under the table and it's never been dealt with by the panel properly."
Mr Umunna said the resignations of a number of inquiry lawyers showed there was "severe dysfunction" within its legal team.