PLUM (KDKA) — There are new developments today in the ongoing investigation into alleged teacher-student sexual relationships at Plum High School.

Sources tell KDKA that investigators with the Allegheny County District Attorney’s Office were at the high school late Tuesday morning to serve search warrants.

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The visit by District Attorney Office officials was an unexpected one.

Sources tell KDKA the search warrants were executed within the administrative offices and that this is information pertaining to a grand jury investigation.

While at the high school, KDKA saw men driving official vehicles, hauling out boxes.

Superintendent Timothy Glasspool tells KDKA’s Kym Gable that investigators also took files, images, computer devices and folders.

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He said: “Investigators from the office of the District Attorney issued several search warrants relative to the ongoing police investigation. We just cooperated with anything they requested to get them the information they needed. We are not sure when they will be complete. We expect them back tomorrow.”

Meanwhile, a teacher at the center of one of those investigations, Joseph Ruggieri, will not face a district judge tomorrow. Ruggieri waived his preliminary hearing.

He appeared at Magistrate Linda Zucco’s office Tuesday morning to file the paperwork with his attorney.

The most serious counts against him are felony charges of institutional sexual assault.

Stay with KDKA for the latest on this developing story.

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