Three paedophile teachers worked together at the same school in Essex before their crimes came to light.
Lee Brumby, Thomas Rodgers and Craig Keane all worked at Mayflower High School in Billericay in 2012 before they were convicted of sexual offences against children.
Their crimes did not involve pupils at the school and came after separate investigations, the council said.
Brumby, 64, was headteacher of the co-educational school when he was arrested in 2022.
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He was given a 16-year sentence at Basildon Crown Court last week for five historic sexual offences, including raping a child.
His victim told the court she lived in ‘constant fear’ after the abuse and said she didn’t know if she would ‘ever truly feel safe again’.
Brumby, who once worked at a girls’ school in Southend, was headteacher at Mayflower High School while Rodgers and Keane were teachers there.
The junior teachers were both convicted of sexually assaulting young boys and were charged after leaving the school.
Rodgers, who was a music teacher at the school in 2012, was jailed for four years last year for sexually assaulting two boys in the 1990s.
He was convicted of indecent assault and two counts of indecency with a child for the assault when he was 17 or 18.
Keane was jailed in 2017 and worked as a design and technology teacher at the school.
He admitted nine charges of sexually assaulting a child under 13 the previous year.
All nine charges related to a single evening on October 2, 2016, in what the NSPCC called a ‘devious and depraved attack’ on a vulnerable young boy.
The charity said it was ‘beggars belief’ that he ‘committed such vile crimes while holding positions of responsibility’.
Keane was working as a special constable in the Met when he was arrested and had access to indecent images of children.
A council spokesperson said: ‘These are three completely different criminal investigations that are not linked in any way to any children, past or present, at the school.
‘While the three individuals worked at the same school for around two years, there had been no allegations, arrests or convictions before or during this time.
‘There is absolutely no way that the school would have been able to predict these allegations, arrests or convictions and a full vetting process would have been completed for each before they were recruited.
‘Two of the individuals were not employees of the school when they were arrested. Both were arrested sometime after they had left the school.
‘When allegations were made about Lee Brumby, he was suspended immediately.’
They added: ‘The school has kept parents and carers informed throughout and have offered support to anyone that may need it.
‘The school has strong safeguarding arrangements in place, underpinned by policies which adhere to statutory and local guidance, all of which are regularly reviewed’
A spokesperson for Mayflower High School said: ‘In 2023, a new headteacher and leadership team were appointed to guide the school through a new chapter of growth and improvement.
‘Since then, we have introduced a number of significant changes across all areas of the school.
‘The safety and wellbeing of all of our pupils will always be our highest priority. We are committed to providing a safe environment for all of our pupils.’
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