(Image credit: Collin County Jail)

A Texas dad terrified his child's elementary school when he decided to conduct a "rogue" security drill to see how the school would respond in the event of an emergency, according to the school district.

Ron Miller, 44, entered the office of the Celina Elementary School at 7:50 a.m. on Wednesday, according to police, where he "conducted his own drill to test the school's response to an active shooter situation."

"Although Miller did not display a weapon, the statements and actions of Miller were aggressive and created panic and fear among the school's staff," the Celina Police Department said in a news release.

Police rushed to the school. Miller was arrested later in the day.

Celina Independent School District superintendent Donny O'Dell sent a letter to parents on Thursday saying that the school did not believe at any time that the students were "in harm's way," but, as a precaution, a police officer was positioned at each of the district's campuses for the rest of the day.

"We have always had a security plan in place that involved our police officials," O'Dell wrote. "However, because of recent events we have ramped-up our security efforts on all campuses."

O'Dell may have been referring to the Dec. 14 shootings at Sandy Hook Elementary School in Newtown, Conn., where police say Adam Lanza, 20, went on a rampage that left 20 children and six adults dead in the school. Many schools across the country have increased security since the massacre.

Miller was arrested and charged with terroristic threat, which is a third degree felony. He is being held on a $75,000 bond.