MOORE, Okla. -- New details are emerging about a frightening incident at a Moore elementary school.
Monday morning a loaded gun was found on a teacher's chair.
An Oklahoma City man has since been charged with bringing a gun onto school grounds, a felony.
Wednesday he turned himself in at the Cleveland County jail.
The suspect is the husband of one of the school's teachers.
He said he went to school to help his wife with some computer issues on Sunday and simply forgot he had his handgun with him.
"He says he was cleaning his house and put the gun in his pocket and went to school. That's where it fell out of his pocket," Moore Police Sgt. Jeremy Lewis said.
Only after the school went on lockdown did 57-year-old Mark T. Brim realize the suspicious gun belonged to him.
According to court records, "Brim has an expired conceal carry license and advised he would never intentionally take his gun onto school property."
That mistake still led to a felony charge.
"By taking the gun into school it was a danger and that's what the charge is for," Lewis said.
"Everybody has heard that ignorance of the law is no excuse," attorney David McKenzie said. "It is unlawful to bring a firearm to school property."
McKenzie said even if Brim didn't mean to commit a crime, he could still be held accountable.
"If he knew, or should have known, he could be culpable of that or guilty of that," McKenzie said.
"Even though he didn't mean to have an expired license or mean to take the gun to school, It is a crime," Lewis said.
Brim is free on a $5,000 bond.
The felony weapon charge carries a maximum of two years in prison.