Students returned to class following a gun threat call that caused a lockdown of Port Townsend High School Thursday morning.

An anonymous caller threatened to bring a firearm to Port Townsend High School, prompting the school to be put on lockdown at 10:25 a.m. Thursday morning.

According to the Port Townsend Police Department and the Washington State Patrol, the caller altered their voice, threatened to shoot up the school, and played what sounded like fake gunshots from an assault rifle in the background of a call to JeffCom 911.

During the call with JeffCom 911 that was received by emergency dispatchers at 10:15 a.m., the anonymous caller played what “sounded like a fake AR in the background,” said Trooper Simon Hovinghoff of the Washington State Patrol.

The call “caused an immediate response” from local law enforcement agencies, Port Townsend Police Chief Thomas Olson said.

The Washington State Patrol, Port Townsend Police Department, and Jefferson County Sheriff’s Office arrived at the school and set up a lockdown perimeter around the campus at around 10:30 a.m.

The lockdown was called off, with the perimeter being lifted just after 11 a.m.

The threat was directed at Port Townsend High School, with no other schools in the district being put on lockdown.

The school district enacted multiple safety measures in response to the lockdown, which included immediately locking all entry points to the high school, making an announcement to students, and directing all students and staff inside.

“The PTHS campus is no longer in modified lockdown. Classes and transitions are resuming as normal,” Superintendent Linda Rosenbury wrote in an email update to students, parents, and guardians. “The principal briefed all staff on the incident to prepare them to support students. All students were invited to go to the auditorium during lunch if they wanted to process together.”

Thursday's incident followed one made to other schools in Jefferson County and across the state in recent weeks. The Chimacum School District evacuated its campus in mid-April after receiving an email threat.

A similar threat of a shooter was also received by emergency call centers in Eastern Washington Wednesday.

“Schools across the state have received similar threats from a similar phone number this week,” Rosenbury said.

“A similar threat was investigated in Kitsap County this morning. So far these calls have not been led to any violence,” she added.