MARTINEZ -- An Antioch man who terrorized Contra Costa County schools with explicit threats of violence in October 2011 pleaded no contest to the charges Wednesday and was sentenced to five years, four months in state prison.

From inside a courtroom holding cell, Larry Bantola, 38, pleaded no contest to seven counts of making criminal threats and seven counts of false impersonation -- all felonies. Bantola made the threats in the name of an acquaintance whom he wished to discredit.

In addition, Bantola was ordered to pay restitution to be determined at a later date. It is possible restitution could be substantial, since his threats caused hundreds of students to stay home from school and resulted in the loss of thousands of dollars in attendance-based state funds.

Bantola, who will receive credit for the 849 days he already has spent in custody, could be eligible for parole after serving four years, six months. He spent more than one year at Napa State Hospital after being found incompetent to stand trial in June 2012. His competency was restored during a training program in Napa.

Meanwhile, letters written by administrators of the affected schools to various law enforcement agencies, released Wednesday by the Contra Costa District Attorney's Office, reveal the impact Bantola's threats had on educators, students and parents.

His first target was Alhambra High in Martinez, which received a fax on Oct. 13. The fax, wrote then-principal Nermin Kamel, "indicated that the school would be a victim of a Columbine type incident on Oct. 14, 2011."

Student attendance on that day was down 40 percent, Kamel said, costing the school $32,200. The school also paid $4,000 for increased security and clerical staff, and a consultant. "To each of us this threat was material, substantial and personal," Kamel wrote.

One week later, Concord High received a fax threatening a shooting on campus on Oct. 21. Principal Gary McAdam wrote that the threat caused "widespread fear not only for our students, but parents, teachers and staff." He said more than 1,000 students were absent from school on the day of the threat.

On Oct. 26, letters were received at three Martinez schools -- John Swett Elementary, and private schools St. Catherine of Siena and White Stone Christian Academy. Marj Pampe, John Swett's principal at the time, described the letter as "vulgar, explicit, pornographic content in a pedophile's language expressing what the author intended to do to young girls at John Swett."

White Stone Christian Academy is a home-based school. Administrator Susan Tunison said the letter had her "immediately double bolting the doors."

One day later, Valhalla Elementary in Pleasant Hill and private New Vistas Christian School in Martinez received threatening letters.

"As you can imagine," wrote administrator Maria Zablah of New Vistas Christian School, "this incident created stress, concern and an overall eerie feeling."

Contact Gary Peterson at 925-952-5053. Follow him at Twitter.com/garyscribe.