ST. LOUIS COUNTY, Mo.—Prosecutors on Monday charged Matthew McCulloch, a St. Louis County Police officer and son of the former St. Louis County Prosecuting Attorney, with 11 counts after he was arrested Sunday for firing approximately a dozen shots at a Kirkwood School District trunk or treat event.

McCulloch was charged with four counts of endangering the welfare of a child, five counts of armed criminal action, one count of the unlawful use of a weapon and one count of a terrorist threat. He's being held on a $500,000 cash-only bond.

Kirkwood police say McCulloch caused a disturbance at North Middle School Sunday afternoon which hosted the Halloween event for Tillman Elementary School. According to the charging documents, Kirkwood police say McCulloch "aggressively approached numerous attendees at the event and made statements such as "you are all going to die."'  According to the probable cause statement filed by police, McCulloch was shoved to the ground, got up, then pulled his shirt up to display a handgun and a badge, firing off roughly 12 shots while shouting that the people would die. 

Police say witnesses tackled McCulloch and took his weapon.

No one was injured.

St. Louis County Police confirmed earlier Monday that an officer off duty had been arrested and put on administrative leave.

"We were disappointed to learn that the actions of one of our officers caused a disturbance in the City of Kirkwood on Sunday. In a profession where we are called to keep the peace, this display of disregard for safety is concerning. We are very grateful that no one was hurt," Chief Kenneth Gregory said in a statement released after charges were filed.

McCulloch's father, Robert, the longtime St. Louis County Prosecuting Attorney who left office after his primary defeat in 2018, issued a statement Monday before charges were filed.

"​Please know that we will be eternally grateful that no one was physically injured. However, we also a painfully aware that an incident such as this can and does cause significant emotional trauma to those, especially children and their parents, who witness such an event. Our thoughts and prayers are with those victims," McCulloch's family said in a statement expressing confidence in the Kirkwood police department's ability to "conduct a complete and thorough investigation."

Classes Monday at Tillman Elementary School were canceled. Instead, the school was open for students, families and staff who need support from school counselors or social workers. 

“We are deeply grateful for the lack of injuries but acknowledge that this traumatic event will reverberate through the school community during the coming days, weeks, and months,” the school district said in a social media post Sunday.

A district spokesperson told Spectrum News that the district does expect to hold classes there Tuesday. 

Matthew McCulloch's bail conditions include an order to have no contact with victims or their families, could not possess firearms or alcohol and would need a mental health evaluation. 

A statement from Prosecuting Attorney Wesley Bell's office said McCulloch's status as a county police officer and his relationship to the former prosecutor would not be a conflict in the office's handling of the case.

"We are a professional office of prosecutors who review all cases in light of the evidence and the law and treat all defendants fairly, justly and equally," the statement said late Monday.