Seven students were reportedly suspended from Maria Carrillo High School for possessing copies of a key that gave them access to campus facilities where students allegedly smoked marijuana and had sex.

One student with knowledge of the situation said more copied keys may exist despite officials' insistence that all keys are now accounted for.

Principal Rand Van Dyke declined to answer questions about the suspensions and the possibility that copied master keys that unlock all doors on campus are still floating among the student body, referring inquiries to George Valenzuela, attorney for Santa Rosa City Schools.

"Earlier in the 2012-13 school year, a group of students misappropriated a school key at Maria Carrillo High School," Valenzuela said. "The school key and all of the copies of the school key have been recovered. Appropriate disciplinary action was taken regarding the students involved."

"The district cannot comment further as this is a confidential student matter," he said.

But the reporter who broke the story in the school newspaper said that because multiple keys were passed around and loaned among students, he believes other keys may exist, posing a liability concern for the district.

"I was told by a student who was involved that it was entirely possible that there may be more," said Colin Metcalfe, a senior at Carrillo and a reporter with the Puma Prensa who wrote a front-page story in the paper's Feb. 7 issue.

"Those keys had no 'Do Not Duplicate' on them, so a keysmith wouldn't have any idea not to duplicate it," he said.

Valenzuela said that, after interviews between students and Maria Carrillo administrators, school officials felt that all the copied keys had been accounted for.

"The principal felt that they were all recovered," he said. "They were pretty honest."

Valenzuela said he had not heard reports of the existence of additional keys and couldn't confirm if the allegations are valid.

"If there are other keys out there, then they should re-key the school," he said, indicating the process of changing every lock on campus.

The cost of re-keying a high school campus could run between $25,000 and $30,000, according to Jennie Bruneman, director of maintenance and operations for Santa Rosa City Schools.

The responsibility could be assigned to parents of the disciplined students, Valenzuela said.

Metcalfe reported that seven students were suspended from three to five days over the incident. Valenzuela would not confirm the number of students or the length of their suspensions, citing student confidentiality.

No staff members were disciplined.

District officials did not say how students initially came to possess a master key.

The keys in question reportedly gave students access not only to classrooms but to all of the main buildings on campus.

The newspaper reported that, while keys were used by students in the school's music program to retrieve band gear or access equipment, they also were used to enter practice rooms where students smoked marijuana in enclosed spaces or "hot boxed" in order to amplify the drug's effects. Another pair of students reportedly had sex in a band practice room.

"I think most of them used it for legitimate reasons. They are all fairly committed musicians," Metcalfe said. "The students who were disciplined and the students who were suspended, they weren't actually involved in the hot boxing."

Staff Writer Kerry Benefield writes an education blog at extracredit.blogs.pressdemocrat.com. She can be reached at 526-8671, kerry.benefield@press democrat.com or on Twitter @benefield.