A science teacher who sexually assaulted one of his pupils has been jailed for more than nine years, as his victim told a court she was "haunted by nightmares of" his confessions.
The investigation into Mark Langford, 55, began in November 2021 when Google sent a report that he had stored child abuse material on its platform.
National Crime Agency (NCA) investigators identified the former teacher and arrested him at his home in Beccles in Suffolk.
Further inquiries revealed that he had groomed and sexually abused a 15-year-old pupil he taught at a Suffolk school in the mid-2000s.
NCA officers found a letter Langford - now of North Yorkshire - had written to his victim in April 2022, instructing her what to say if she was questioned by the lead investigator.
In it, he pleaded with her to "not give him any accidental ammunition against me".
"You can tell him you know I’m a porn addict, and that I was arrested for having indecent images of children.
"Don’t forget the “arrested for” bit – don’t say I did it, or that I confessed to you, because that might drag you into court as a witness. I don’t know if it will, but that’s not a question I dare ask him.”
Before being arrested Langford told officers: “It’s all in there, I know what you’re looking for, I’ve made a mistake and ruined everything”.
He had 2,718 indecent images of children on his devices, along with 199 prohibited images and 109 extreme images.
There was also evidence of Langford discussing child abuse with others online, and offering advice about abuse.
Langford taught at Suffolk and Norfolk secondary schools from 1996 until just after his arrest, at which point he was employed by a free schools trust which runs schools in Beccles, Bury St Edmunds and Saxmundham, said the NCA.
He admitted charges including indecent assault, indecency with a child, perverting the cause of justice, indecent images of children offences (making, possession and distribution) and possession of extreme pornographic images at Ipswich Crown Court in July.
On Tuesday he was jailed for nine years and two months and given an indefinite sexual harm prevention order.
In an impact statement read to the court, the victim said: “His manipulation, deceit and devious nature unnerves me as he is not the man he presented himself as for many years.
“What Mark needs to grasp is that I am thoroughly appalled and disgusted by his actions and haunted by the abuse I suffered at his hands…He disgusts me to the core and I am haunted by nightmares of the confessions he told me.
“I still feel I am carrying around his filthy secret that he expected me to keep for him. This repulses me that he thought I would prevent the course of justice …
“I am appalled, insulted and disgusted by everything he has told me and these confessions will stay with me for a long time. He has not only abused my body but my mind too.”
NCA operations manager Holly Triggs said: “Mark Langford was a cowardly and scheming offender.
“Not only did he abuse his position of trust, he asked his victim to stay quiet about his offending and the horrific conversations he had with other paedophiles online.
“The NCA works relentlessly to protect children from sexual abuse and ensure that those who abuse them face justice.”
Langford was dismissed by his employer in January last year.
Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know