The Federal Bureau of Investigation has said that hundreds of people have contacted its agents about paedophile teacher William Vahey, who is suspected of drugging and molesting boys over a forty-year period, the Associated Press has reported.
The US Bureau has said that it has now "been contacted by several hundred individuals from around the globe."
Vahey killed himself at age 64 after evidence of child molestation was found on one of his memory drives.
Several families have told police that they do not wish to be informed of details surrounding potential sexual abuse of their children at a London school between 2009 and 2013.
The Metropolitan Police has identified images of suspected abuse against at least 60 boys aged between 11 and 16 from the period paedophile teacher William Vahey taught at Southbank International School.
Commander Graham McNulty, Specialist Crime Investigations, said: "A significant number of parents have indicated that they do not wish to be informed of any details pertaining to possible offences against their children.
"We respect this position and the dilemma that parents face. We are therefore currently considering differing options which would allow us to account for the wishes of all parents whilst ensuring we fulfil our responsibilities to support victims of crime."
A former pupil of London's Southbank International School said that he was "most likely" a victim of paedophile teacher William Vahey, who admitted to drugging male pupils before sexually abused them on school trips.
Vahey, 64, committed suicide last month and the FBI has warned that because of the methods he used, pupils may not be aware they were victims.
The boy sat alongside his mother as he told The Guardian about a school trip he went on with Vahey, during which he began to feel sick after dinner.
"I was drifting in and out of sleep," he said. "I told one of the chaperones and it was decided Mr Vahey was going to bring me back to the hotel."
"He took me to my room," said the boy, who has not been named. "As he was taking me to bed he asked me: 'What are you going to wear to bed?' I found the question and his manner to be very odd. I remember being completely out of it."
The boy's mother added: "We feel a lot of rage and we feel betrayed by the school."
An investigation into the teacher uncovered up to 60 images of students at the prestigious school on his computer.
Natalie Salmon was a student at a Venezuelan school where paedophile William Vahey was a teacher.
She told ITV News it is "really scary" that some of Vahey's victims may not know they had been assaulted, as they may have been drugged at the time.
She added she "can't believe" the teacher "got away" with his campaign of abuse for so long.
Vahey, who died in an apparent suicide, had been a teacher at several international schools across the world. The Southbank International School in London has confirmed that images of between 50 and 60 of its students were found on Vahey's computer.
Vahey was convicted over a child sex offence in California in 1969 but appears to have failed to sign the sexual offenders' register, which allowed him to slip through the net and go on to work in several schools.