FBI investigates teacher William Vahey over UK abuse
One of London's most prestigious private schools is cooperating with the FBI to identify dozens of children thought to have been abused by a teacher.
William Vahey, an American citizen, taught students at Southbank International School from 2009 to last year.
He was found dead last month after images of up to 90 students were found on his computer.
Reeta Chakrabarti reports.