Analy High School teachers were able to identify the handwriting of a 16-year-old student Wednesday, leading to his arrest for allegedly penning a threat of violence on a bathroom wall at the school a day earlier, Sebastopol police said.

“After teachers looked at the handwriting it quickly came down to a single suspect,” said Sebastopol police Lt. Greg DeVore.

The teen admitted to the threat marked on the second floor of the main campus building during an interview with law enforcement, DeVore said. He was arrested on suspicion of making felony criminal threats and booked in Sonoma County juvenile detention.

After the threat was discovered Tuesday morning the West Sonoma County Union High School District decided to send all 1,100 students home early out of “maximum precaution” and concern over their emotional well-being, said Assistant Superintendent Steve Charbonneau.

“In light of what happened in Florida, it puts everyone on edge,” Charbonneau said.

Most students returned to campus Wednesday, where Charbonneau said it was “business as usual” despite a visible police presence. He did not have attendance figures to show how many students were not on campus.

Uniformed Sebastopol police officers had a “highly visible presence” at Analy High School on Wednesday, said DeVore, who would not disclose the specific number of officers deployed to the campus.

“We want students and the parent of the students to feel safe,” DeVore said.

Although an arrest has been made police will remain on campus for the next few days, he said. Counselors also are available for students who need them.

“It is difficult to go back to school even when you find out when something like this is not a credible threat,” Charbonneau said. “You have to be sensitive and responsive to student and staff needs.”

The message was written in permanent marker sometime between 7:15 and 7:45 a.m. and was discovered at 8 a.m., Superintendent Steven Kellner said Tuesday. Officials declined to say what was written.

Charbonneau said it was believed from the start that a student wrote it.

“That would be our first inclination,” he said. “The time frame that the message was left was a time when students have access to the bathroom.”

A similar threat was made at Alameda High School in Alameda. Someone reportedly left on a bathroom wall a message that threatened violence would occur Tuesday. The message was discovered Monday, and school was kept open.

You can reach Staff Writer Eloísa Ruano González at 707-521-5458 or eloisa.gonzalez@pressdemocrat.com. On Twitter @eloisanews. You can reach Staff Writer Nick Rahaim at 707-521-5203 or nick.rahaim@pressdemocrat.com. On Twitter @nrahaim.

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