The suspect, 48-year-old Matthew Serwedes, was a teacher at Carl H. Kumpf Middle School.
Serwedes is accused of possessing and distributing child sex abuse material via social media and a messaging platform.
An investigation led authorities to arrest Serwedes at his home.
Police seized electronic devices for forensic analysis.
In a statement from the Clark Public School District, they said it doesn't believe the teacher involved any of his students.
The school district said the teacher was immediately suspended.
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