Scripture Union could have done more to protect young people from abuser John Smyth, an independent review has found.
The executive summary of the review, published this week, found that three members of staff were aware of the "dreadful" abuse committed by the late QC but did not make it known to the wider organisation.
Their employment with Scripture Union was funded by the Iwerne Trust, a charity chaired by Smyth that ran evangelical camps for boys and young men.
Many of Smyth's victims became acquainted with him through these camps. Smyth was also a trustee of Scripture Union during the 70s.
The report echoed the findings of previous investigations, with accounts of beatings and "extreme violence", as well as "consistent and clear indicators of grooming and sexual framing".
But the abuse was not reported by Iwerne to the police until 2013, by which time Smyth was in Africa where more boys fell victim.
According to the report, the Titus Trust, successor to the Iwerne Trust, first informed Scripture Union of non-recent abuse disclosures relating to Smyth in 2014, and this information was shared with Scripture Union Trustees.
The report said it was a "clear" failure in safeguarding and governance that SU did not report the concerns to the police as soon as it became aware of them.
It also said that victim accounts together with the volume of evidence made it "implausible that no senior SU staff were aware of the concerns surrounding Smyth's continued abuse of boys in Africa".
The report also criticised former SU National Director Rev Hastie-Smith, saying that "a lack of professional curiosity appears to underpin the explanations given as a rationale ... for why concerns about John Smyth were not pursued by him or others or were easily dismissed".
"Revd. Hastie-Smith states that by his own assessment, he must have been either 'grotesquely insensitive' or 'extraordinarily incurious' as he had never become aware of anything nor did he ask any questions prior to 2014," the report reads.
"Victims stated that they felt there was a level of 'willful ignorance' demonstrated by the wider evangelical community and that 'seemingly comprehensive accounts were actually studies in obfuscation'."
The full report is to be published later this year. A separate investigation is also being carried out by the Church of England.