Prosecutors said that two girls appearing in the images have been identified as Parkland High School students. Contrary to an initial report, they said another girl seen having sex with a boy in a video had not been identified and they are unsure what school she attends. The boy also remains unidentified.
The two Parkland students shown exposing themselves are 14 and 17, said Matthew S. Falk, Lehigh County's chief deputy district attorney.
Both girls took the pictures of themselves.
"They transferred the photographs to someone else at school," Falk said. "What I don't think they anticipated was the widespread dissemination of those pictures."
County prosecutors contacted about 40 students and their parents, asking that the students come forward to show that the images had been deleted from their cell phones. They gave them until Tuesday to meet with a trooper at the high school. About 15 students turned over their phones for inspection on Thursday.
Because the girls are underage, anyone who holds onto the images could face charges of possessing child pornography, prosecutors said.
Students at the suburban Allentown school have said the images were widely transmitted starting about two months ago and reached far more than the 40 students authorities contacted. Prosecutors said they realize they would not be able to ensure all the pictures are deleted.
Falk said an investigation continued and that "as we continue our investigation things are becoming more clear."
