(CNN) -- A drug counselor at California high school pleaded not guilty Wednesday to secretly videotaping students engaged in sexual activity with each other, and to possessing child pornography.
Gilbert Olivares, 34, turned himself in late Monday, according to his attorney and the Salinas Police Department. His bail was set at $1 million.
He entered his plea in Monterey County Superior Court to 19 felony charges brought by the district attorney.
Allegations include lewd act upon a child, contact with a minor for sexual offense, possessing child pornography and using a minor to do or assist prohibited acts, according to the criminal complaint.
Olivares' attorney, Andrew G. Liu, said he could not comment on specifics of the charges and his client's stance.
"We are at a very early stage," Liu told CNN. "I have just received 71 pages of police reports and I have not had time to review them yet."
Olivares was first arrested last week at Salinas High School, initially on 11 charges, according to authorities. Olivares posted $50,000 bail at that time and was released, according to police Sgt. Christopher Lane.
The criminal complaint alleges Olivares inappropriately touched the buttocks of a 14-year-old, identified as John Doe. The two allegedly also had conversations via Facebook.
On further investigation of items seized from the counselor's home, detectives found 14 videos made by Olivares in his office at the high school, police said in a statement.
"The videos are of teenage students engaged in sexual activity with each other within Olivares' office, during school hours," the statement says. "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."
Police said the forensic search of Olivares' computer also yielded dozens of pictures and videos depicting child pornography. They are not believed to depict children who attended the school and were probably downloaded from the Internet, police said.
A new arrest warrant on multiple charges was obtained Monday and bail was increased to $1 million.
"The bail is unusually high and that might be subject to challenge in the future," Liu said.
Olivares' preliminary hearing was scheduled for April 5.
"He is innocent until proven guilty and we're looking forward to a fair hearing in court," said the attorney. "He has the strong support of a loving family."
Olivares is employed by an organization that counsels youth on drug and alcohol abuse, police said. Although he worked as a counselor at Salinas High School for five years, he was not an employee of the school district.