Johannesburg ? A woman accused of abusing teenagers at Oprah Winfrey’s school for girls in South Africa was acquitted of the charges Monday, and Winfrey said she was “profoundly disappointed” by the trial’s outcome.

Prosecutors had accused former school matron Tiny Virginia Makopo of trying to kiss and fondle girls at the school soon after it opened in 2007 outside Johannesburg.

Makopo also had been accused of assaulting one of the teens as well as a fellow supervisor.

“The matron who was working at the Oprah Winfrey school was found not guilty on all the sexual assault charges,” Mthunzi Mhaga, a spokesman for South Africa’s National Prosecuting Authority, said Monday. “The magistrate was of the view that the state had failed to prove beyond reasonable doubt that she was guilty. We won’t be appealing the judgment.”

Winfrey had called the allegations crushing given her own stated history of childhood sexual abuse and promised an overhaul of the school.

“I will forever be proud of the nine girls who testified with the courage and conviction to be heard,” Winfrey said in a statement Monday.

The lavish $40 million Oprah Winfrey Leadership Academy for Girls, which opened in January 2007, aims to give girls from deprived backgrounds a quality education in a country where schools are struggling to overcome the legacy of apartheid.