An Iowa teacher was arrested after she wrote 'threatening notes' about 'committing gun violence' at school, police say

• An Iowa teacher lost her job and was arrested after she wrote a series of "threatening notes" at school.
• Police say Katrina Phelan, 37, wrote multiple notes that mentioned committing gun violence on school property.

An Iowa teacher was arrested after police determined she was the source of a series of "threatening" handwritten notes that mentioned committing gun violence on school property.

Katrina Phelan, 37, was arrested and charged with three felony counts of threats of terrorism, according to Council Bluffs Police Department. Phelan, who was a teacher at Abraham Lincoln High School, turned herself in to the Pottawattamie County Jail on December 1.

"Council Bluffs police detectives conducted an investigation into a series of anonymous handwritten notes found inside the school, all making reference to committing gun violence upon school property," a press release from the police department reads. "Each of the notes were reportedly either found in Phelan's classroom or found by Phelan herself, in various locations within the school.

According to court filings, the notes were discovered November 18, 19, and 23.

"When interviewed, Phelan admitted to writing the notes. It was determined that she had no intentions or means of carrying out these threats. In at least one of the notes, Phelan, posing as an unnamed student, wrote that she was tired of being made fun of," the press release said.

Phelan said she wrote three of the four notes, but that she did not recall writing them, according to an affidavit cited by KETV. She said she wrote the notes "out of concern, worry, and frustration over the lack of control of her classroom," the affidavit said.

Jon Joseph Narmi, an attorney listed for Phelan, did not immediately return Insider's request for comment Saturday.

The high school cut ties with Phelan, telling parents in a letter that the source of the "threatening notes" was a school employee.

"The employee has been charged with a crime, has voluntarily surrendered to the police, and will no longer be employed by the Council Bluffs Schools," Principal Bridgette Bellows wrote in the letter, seen by KETV. "We want all students, parents and staff members to have confidence that our schools are safe and supportive environments."

Phelan faces up to five years in prison for each of the three felony charges against her.