Police in Allentown, Pennsylvania have tried to curb the spread of a pornographic video of two U.S. high school girls which were being distributed via mobile phones to classmates and later to others.
At least 40 students attending the school have been ordered to present their phones for inspection to ensure the images have been deleted.
One student said the images showed a girl performing a sexual act with her boyfriend but was unable to say if the girl knew she was being recorded.