Her academy was supposed to give the poorest and brightest girls in South Africa a clearer shot at life. Yesterday, however, Oprah Winfrey was forced to defend the school, while a dormitory matron appeared in court to face charges of physical and sexual abuse of students.

Winfrey, who was raped by a cousin when she was 9, told how she broke down and wandered from room to room in her home when she first heard about the alleged abuse. “It has shaken me to my core. It has been the most devastating experience of my life,” the chat show host said.

Winfrey, America’s highest paid television star and the richest African American, invested £22 million from her charitable foundation in the Oprah Winfrey Leadership Academy for Girls. But since its opening in January – which was attended by the singers Mariah Carey and Tina Turner, the film director Spike Lee and other celebrities – the school has been dogged by controversy.

Some parents complained that its strict rules were comparable to a prison regime and criticised the tight security measures that Winfrey had insisted were made necessary by South Africa’s high rates of violent crime. Local residents complained that they were not given cleaning and cooking jobs, and police officers resented the fact that private firms were responsible for security.

Winfrey addressed journalists by satellite link yesterday soon after Virginia Mokgobo, a former dormitory warden at the school, appeared in Sebokeng Magistrates’ Court on charges of assault, indecent assault and causing criminal injury.

One girl was reportedly grabbed by the throat and thrown against a wall, while others are alleged to have been beaten and hit on numerous occasions. The details of the alleged indecent assault have not been made public, but Ms Mokgobo is accused of soliciting underage girls to perform indecent acts.

Police are investigating at least three serious cases of indecent assault, spanning a four-month period.

The former matron was released on bail of 3,000 rand (about £220) and the case was postponed until December 13 for further investigation.

Winfrey promised a complete shake-up at the school. “We are removing the dorm parents and, as I have said to the girls, cleaning house from top to bottom,” she said. She also confirmed that she was not renewing the headmistress’s contract and would dismiss employees who she believed had tried to hide from her the facts of the case.

Pupils had told her that they were ordered to “put on happy faces” when she was there and not to complain, she said. The girls had “cheered and cried” when she told them that the dormitory wardens had been replaced with a rota of teachers. “All the girls were afraid of repercussions from the remaining dorm parents. A horrible situation has been uncovered and driven out. We are moving on.”

She praised the girls for coming forward together in a group to report to the school director the alleged incidents. “They reclaimed their voice,” she said. “Those are the types of leadership qualities we hoped initially to foster at the school.”

A group of the girls are receiving counselling. She confirmed that she was buying every one of the 150 pupils a mobile phone with which they could call her personal number any time they wished.

She said that because of the high rates of rape and sexual abuse in South Africa she had worked hard to ensure that outsiders would not be able to reach the students. “But as is often the case, child abuse, sexual abuse happens right within the family, right within the confines of people you know,” she said.

Ms Mokgobo, 27, faces 13 charges against six students aged between 13 and 15. She entered a plea of not guilty during the bail application and as the charges were read out she twisted her braided hair and fought back tears.

The school is in Henley-on-Klip, a tranquil town south of Johannesburg characterised by quaint mining cottages. The 28-building campus, built over 52 acres, resembles a luxury retreat, complete with classrooms, computers and science laboratories, a library and a theatre.

Winfrey helped to choose the first entrants from 5,000 applicants and has built a house for herself in the school grounds. The girls had to show academic and leadership potential and have household incomes of less than £350 a month in order to be eligible to attend.

Measure of success

1954
Oprah Winfrey was born to unmarried parents. She was raised by her grandmother on a farm without running water

$260m
What she earned between June 2006 and June 2007

30m
Number of people who watch her weekly TV show

1
Her position in a 2007 list of the world’s most powerful celebrities

Source: Times database

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