WICHITA, Kan. (AP) -- A Kansas military boarding school embroiled in a lawsuit alleging widespread abuse of cadets ordered its students last week to surrender their cellphones, and a staff member reviewed photos and videos stored on them and then deleted hundreds of images related to the school, according to a document filed Monday in federal court.

Lawyers for seven former cadets who sued St. John's Military School in Salina allege that one of the deleted videos showed a staff member abusing a student, while others showed abuse of former cadets who have filed suit.

The school, in an email statement to The Associated Press, denied the destruction of evidence related to the lawsuit. St. John's said it has a long-standing policy that prohibits students from taking pictures or recording videos with cellphones, a policy it contends is common for boarding and military schools throughout the nation.

"In the instance that took place recently on campus, a student's phone was confiscated and the video was erased in accordance with the cell phone policy," the school said. "This situation is in no way related to ongoing litigation and did not involve any of the plaintiffs."

Daniel Zmijewski, the plaintiff's attorney, filed the motion in U.S. District Court in Kansas and is seeking a court order to protect any remaining photos and videos or evidence in any electronic medium. He also asked the judge to appoint a computer forensics expert as a "special master" at the school's expense to collect any remaining data and attempt to recreate the deleted material.

U.S. Magistrate Judge Kenneth Gale has scheduled a telephone conference Thursday with attorneys to discuss how to proceed with the request.

"St. John's continues to thumb its nose at this Court by ignoring its obligations and letting chaos reign at its school," Zmijewski wrote in the filing. "A month after this lawsuit was filed, another boy was branded at St. John's and boys continue to check into the hospital for various reasons."

The plaintiffs -- who are from California, Florida, Tennessee, Colorado, Texas and Illinois -- allege in a lawsuit filed in March that St. John's allowed higher ranking students, called "Disciplinarians," to abuse students, even in the presence of faculty members. The school has settled nine previous abuse lawsuits filed since 2006.

One plaintiff alleges that during the four days he attended the school, he suffered repeated abuse and broke both legs. Another says a ranking student kneed him in the face and broke his eye socket. And a third says he was bound, gagged and beaten by several students, and that photos of the abuse were posted on Facebook.

St. John's, which charges families nearly $30,000 per year for students in grades 6-12, has denied that a culture of abuse exists and notes that each student is required to sign an anti-hazing pledge.