COLUMBIA, Mo. – Numerous iPads issued to students and staff in Columbia Public Schools are now evidence in criminal investigations, and police are using them to determine who did what, and when.

Officials with the Boone County Cyber Crimes Task Force and the Columbia Police Department have seized a total of about 30 school-issued iPads over sexually charged texts and pictures involving both students and staff, KOMU reports.

MORE NEWS: Know These Before Moving From Cyprus To The UK

“Each case is different, but for the majority it was sexual exploitation of a child in some form or fashion,” Boone County detective Tracy Perkins told the news site.

The sheriff’s department is currently in possession of 10 school iPads, while Columbia PD has confiscated roughly 20 devices, though not all were seized because of sex-related problems.

“Some cases may not involve the child at all, other than they were able to catch video evidence of an adult on adult crime on their school-issued device,” Columbia police officials told KOMU.

ABC 17 initially highlighted a problem with students using their school iPads for inappropriate sexual content in April, and district officials reportedly tightened its cyber security and installed new internet filters to keep students on task.

But the news site reports issues with students sending sexually charged texts through the iPads remains an ongoing problem.

“They are also in a situation where they’re sending inappropriate sexually graphic pictures of themselves,” Perkins told ABC 17. “In every situation it’s a little bit different.”

MORE NEWS: How to prepare for face-to-face classes

School officials discussed the issue with the media last Friday, though they provided little context on how big of a problem the sexting has become.

“It’s unrealistic to expect that these young individuals are always going to make good choices,” CPS spokeswoman Michelle Baumstark told KOMU. “There will always be at least one in the grup that potentially makes a bad choice.”

She said the district can restrict capabilities for each device, such as the camera, and can track students’ internet browsing history. The district issues 12,000 iPads to students each year, and they’re required to sign a technology usage agreement that acknowledges the devices will be monitored while they’re at school.

Baumstark said parents can also restrict how their children use the iPads.

“The point of this is for it to be a partnership between not only the school district but also families because students can take these home,” she said. “Parents need to feel empowered to be able to add their own restrictions onto what students can access.”

“Baumstark said the district gives iPads to all classroom teachers, every fifth and sixth grade student, all students at Battle High School and students in Advanced Placement classes at Rock Bridge and Hickman high schools,” KOMU reports.

Anyone, including students, who send nude images of underage students can be charged with distribution of child pornography, though students who engage in that activity are usually not charged, and instead turned over to their parents, police said.

“We’re talking about intervention and getting the behavior stopped, because if we don’t, it will continue,” Perkins said.