A teacher in Washington state was arrested Wednesday after threatening to shoot students, the Pierce County Sheriff’s Department said.

The teacher made the threat while on the phone with a caseworker, according to sheriff's officials.

The woman has not been named by officials, who said she is a 58-year-old teacher at Emerald Ridge High School in South Hill.

She made the statement Tuesday while talking to a caseworker, who called the sheriff’s office around 6 p.m. to report the threat, the sheriff’s office said in a statement.

The sheriff’s school resource deputy assigned to the high school, which is in Puyallup, contacted the teacher at her home, and "the teacher repeated the threat to the deputy and was placed under arrest," the sheriff’s office said.

The teacher was booked on a charge of threats to injure. Pierce County sheriff’s Detective Ed Troyer said that the teacher "didn't back off from those comments" as officials were conducting the investigation, according to NBC affiliate KING of Seattle.

No weapons were recovered, and deputies immediately notified the school district. Troyer said it was unknown what prompted the the threat, the station reported.

"Everybody knows you don’t talk about guns or make any threats in school," Troyer said, according to the station. "If the student does it, they’re going to jail. Now we have a teacher doing it. They're also going to jail, so she’s going to be booked in jail as we look into this a little bit further."

The Puyallup School District said in a statement that "making threats against the safety of students and staff is a felony crime and taken very seriously by Puyallup School District," according to KING.

South Hill is a community of around 52,000 south of Seattle and southeast of Tacoma.