SEASIDE, Monterey County (CBS SF) – A teacher and reserve police officer who accidentally fired a gun at Seaside High School last month during an “educational demonstration” will resign from his position at the end of the school year, according to the Monterey Peninsula Unified School District.

An investigation into the March 13 incident with Dennis Alexander, currently on a leave of absence from both the high school and the Sand City Police Department, is being handled by the Monterey County District Attorney’s Office, Seaside police said.

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“Dennis Alexander submitted his resignation on March 29, effective at the end of this school year,” school district officials said in a statement. “He currently remains on administrative leave while we continue our internal disciplinary process.”

Seaside High teacher Dennis Alexander who shot gun in class (CBS)

Alexander was said to have brought in the firearm for a gun safety presentation. At one point, when it was pointed toward the ceiling, it was accidentally discharged, Seaside police said. Officers arrived at the school, located at 2200 Noche Buena St., just before 1:30 p.m. that day.

After the shooting happened, the school district issued a statement saying that Alexander shooting the ceiling caused debris to fall.  However, the school district’s superintendent did not confirm reports that one student was injured when a bullet ricocheted.

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Students put together a petition in an attempt to help Alexander retain his job two days after the firearm discharge happened, according to the school district.

Seaside police interviewed about 30 people before concluding their investigation and sending the case on to the district attorney’s office, which will determine whether Alexander will face charges.

Sand City police Chief Brian Ferrante said his department will also conduct its own investigation into the incident.

Alexander began with the school district in 1994.

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