A teacher raped by a 15-year-old pupil while marking books in her classroom has threatened to sue her school after it emerged the boy had allegedly tried to rape another teacher.

The pupil, now 16, was jailed for life at the Old Bailey this week after pleading guilty to raping the 28-year-old woman. She had only been teaching at Westminster City boys’ school, London, for two days when the attack happened after the end of the school day.

It was revealed during the trial that another teacher at the school had made a complaint of attempted rape three months earlier, in June last year.

The case did not come to court.

Speaking after the sentencing, the rape victim, who must also remain anonymous, said: “I always said I can’t be the only one who’s been attacked by him. If they had known that, it seems quite clear to me that he shouldn’t have been in (school).

“I am glad the boy has been given a lengthy period of incarceration, not out of vengeance, but to protect others from what I have been through.”

She has said that she will sue the school if evidence emerges that it knew of the boy’s violent history.

The boy is believed to have been in trouble with the police three times during a six-month period prior to the rape.

In March last year, a girl at another school told police that she had been threatened with rape by a gang of youths, including the defendant. The following month, he was arrested after allegedly attacking a woman in south London but was not charged because of insufficient evidence.

During the attack last September, the boy threatened to kill the teacher, struggling with her for 12 minutes, before he forced her to engage in oral sex.

When she ran from her classroom, naked and covered in blood, colleagues were unable to recognise her, the court heard. She had retained the boy’s semen in her mouth, and afterwards spat the contents into a paper cup. The fluid was later used to identify her attacker.

The pupil, who cannot be named for legal reasons, will be eligible for parole after four and a half years, if doctors believe he no longer presents a risk. According to his defence lawyers, the boy was a very intelligent and able pupil, at the top of his class. This was endorsed by the boy’s probation officer.

Reading the sentence, Judge Christopher Moss said: “You subjected your victim to the terror of a physical, sexually degrading and humiliating attack in her own classroom. You left her physically and mentally scarred.”

Speaking after the hearing, the teacher told of her ordeal, but insisted that she will return to the classroom. “I honestly thought that I was going to be murdered,” she said. “I’m going to be very limited in the spheres I can work in, certainly for a few years. But maybe one day I will go back to teaching teenagers, who are an under-appreciated lot.”

Westminster City, whose chair of governors is the academic Lisa Jardine, was inspected in 2001. Inspectors concluded: “Pupils behave well in lessons, showing respect for their teachers.”

Immediately after the assault, the school conducted a full audit of its security, and increased CCTV coverage. A security audit has also taken place across all schools in the authority.

A spokesman for Westminster council said after the hearing: “Violence against teachers of pupils is deplored by the school and the local authority. Although abhorrent, this particular case is an extremely unusual incident. The school now hopes to move forward.”

* adi.bloom@tes.co.uk