NORTH HIGHLANDS (CBS13) — A child porn investigation is under way at Hillsdale Elementary School in North Highlands after students were found passing around an inappropriate photo of a female student.

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After phone calls today, the Twin Rivers School District confirmed over the weekend that the naked photo of a sixth-grader had been sent electronically to some students. This week, other students passed it around.

Hillsdale’s principal Renee Scott-Femenella called in the Twin Rivers Police Department in what is now a child pornography investigation.

One dad, who didn’t want to be identified, was furious with the lack of communication at the school as well as the content of the photo.

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“That is my major concern, is that the school is not communicating with us, the parents.” he said.

Criminal defense attorney Jennifer Mouzis says the children who received and forwarded the photo could face a felony charges.

“This is becoming a very serious issue among juveniles because parents are buying the kids smartphones,” she said.

As parents stood in shock, the district issued a statement that read in part:

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“In an effort to teach students about Internet safety, the Hillsdale principal and a TRDPD officer have met with both sixth-grade classrooms to clearly let students know about the illegality of sending or posting inappropriate photos.”