A 16-year-old male sophomore at McLean High School posted more than 50 explicit photos of female students online, including some of girls who were nude, according to search warrants filed in Fairfax County Circuit Court.

The teenager worked with an older student, a senior at the school, to collect and disseminate photos through the online file-hosting service Dropbox, according to the court documents.

As of Friday, police had not filed charges in the case, which is certain to create waves among students and parents at McLean High, a highly regarded public school in one of the most affluent communities in the country.

The investigation began May 13, when a McLean sophomore told a school resource officer that she had been e-mailed a link to a Dropbox account that was circulating among students, according to affidavits for the search warrants. She opened it and found nude or nearly nude pictures of female students, including some of her friends.

Police were subsequently able to identify 24 folders that contained photos of underage female McLean students posing naked, the court papers say. Authorities said they also found 28 folders containing pictures of young women who have not been identified because their faces are not visible in the photos. All the folders are labeled with female names, according to one of the affidavits.

Information from Dropbox, Verizon and the school system led police to think that the account was created in late January at the home of the male 12th-grader. The senior and another witness identified the 16-year-old sophomore as the primary person behind the account, court papers say. A set of rules found on the Dropbox account informs users that to make any additions, the 16-year-old must be contacted.

Dropbox is a cloud-based storage service that allows people to store content in folders on multiple computers or devices that will update simultaneously when connected to the Internet. Files and folders are visible only to those with whom a link has been shared.

The Dropbox account has been closed, police said.

It’s not clear whether any of the girls pictured knew that their photos would be seen by many other students. In some child pornography cases involving teenagers, victims have given photos to someone they are dating but later found that they were publicly broadcast.

Lucy Caldwell, a spokeswoman for Fairfax County police, said she could not comment on the pending investigation. The search warrants identify the offense under investigation as “possession, reproduction, distribution, and facilitation of child pornography.” The crime carries a sentence of five to 20 years in prison.

“The school has cooperated with the investigation,” said Fairfax schools spokesman John Torre. He declined to comment on any actions the schools might have taken.

Last year, three Fairfax teens were found guilty of felony charges after producing sexually explicit cellphone videos of drunken sex acts with other teens. One was sentenced to three days in a juvenile detention center, the others to 100 hours of community service each.

Anyone with more information about this case or who may be able to identify some of the young women is encouraged to call Fairfax police.

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