A drug and alcohol counselor at a California high school is accused of secretly filming students having sexual encounters with one another in his office, Monterey County officials say.

Gilbert Olivares pleaded not guilty Wednesday to 19 charges ranging from possession of child pornography to performing a lewd act upon a child, the Salinas Californian reported.

The 34-year-old turned himself in on Monday as authorities detained him for the second time in five days, placing Olivares on $1 million bail. The first arrest occurred last week at Salinas High School, where Olivares has worked for the last five years as a representative of Sunrise House, an organization independent of the school district that counsels adolescents on substance abuse. The initial arrest, for which Olivares posted $50,000, was based on 11 charges.

Olivares allegedly allowed the students to have sex in his office while he secretly recorded them in the act, according to KSBW. Authorities found 14 such videos.

"The videos are of teenage students engaged in sexual activity with each other within Olivares' office, during school hours," police said in a statement. "It appears the videos were taken without the knowledge of the victim students and Olivares is not in the room at the time. We continue to work closely with Salinas High School to help identify any possible victims in these cases."

Salinas police Sgt. Chris Lane believes that forensic experts sifting through Olivares' computer files are only beginning to scratch the surface of the case.

"There's thousands of files within that computer, and we're only in the hundreds," Lane told the Montery Herald.

Authorities say that these photos, likely downloaded from the Internet, do not depict students at Salinas High School.

Allegations against Olivares include using a minor to do or assist in prohibited acts, possession of child pornography, contact with a minor for sexual offense and lewd acts upon a child.

Olivares is scheduled to appear in court for a preliminary hearing on April 5.

He faces up to 15 years in prison if convicted.

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