Police arrested student within hours of learning of the threat against Pewaukee Schools

A Pewaukee High School student was arrested Wednesday morning in connection with a threat that prompted the school district to close its campus and cancel classes.

The suspect was taken into custody by investigators with the Waukesha County Sheriff's Department. The investigation has not revealed any evidence of any other actors or participants, according to a joint news release from the Sheriff's Department, the Pewaukee Police Department and the school district.

"We have no reason to believe any threat to the public exists at this time. We believe that this individual worked independently in this threat," the news release stated. It said the investigation is ongoing.

The Pewaukee School District decided to close its campus after receiving the threat on Tuesday night, Superintendent Mike Cady said on the district's website.

A parent reported the threat to police at about 9:40 p.m. Tuesday, March 13. Investigators had the student in custody by 2 a.m. March 14, according to the sheriff's department. No decisions have been made about potentially charging the student, according to the sheriff's department.

The decision to close school was made at about 11:30 p.m. Tuesday, before the suspect was in custody.

The sheriff's department said school will resume on Thursday, but as a precautionary measure, there will be an enhanced police presence to "demonstrate the school's commitment to safety and to ease the concerns of the parents, students and staff."

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Earlier, when announcing the cancellation of classes, Cady said, "As always, the safety and security of our students, families, and staff is our top priority."

In an email, Cady said only key administrative staff would be on the campus Wednesday. He said the threat was made over social media.

At a news conference Wednesday morning, police would not say anything about the threat, where it came from or what it said. Sheriff Eric Severson said he had not seen the text of the threat.

But a screenshot from the app Sarahah.com that was shared on the Pewaukee Parents Facebook page said, "All you liberals are going to be easy targets. I wouldn't recommend showing up to school, unless you want to die. Pewaukee is going to be bigger than Columbine and Florida combined. Just you wait. Pewaukee isn't so safe. ;) - You're all going to die tomorrow and nothing will stop us."

Cady said at the news conference that it would be "premature" to talk about school district discipline against the student, but that potential consequences could be suspension up to expulsion.

Pewaukee High School senior Chloe Sherman said that the latest threat was the fourth one she's experienced since she was in seventh grade.

"Not only is it terrifying, and I can't find myself to fall back asleep, it ruins so much within the school district," Sherman said via Facebook. "In seventh grade, we had to leave school and they cancelled the choir concert. My sophomore year they postponed or cancelled some parts of the homecoming festivities and school (biggest bummer ever) and then we missed our pep assembly last month and now our choir concert will probably be cancelled tonight. Enough is enough," Sherman said.

Julia Westphal, a Pewaukee resident with children in the Pewaukee School District, said in a Facebook post that she was terrified after receiving a call from Cady the previous night. What made Westphal especially worried was that two months before, the school where her husband works had a "kill list" and whoever had written it didn't call the school.

"My kids were terrified that their dad would get killed at work. Now I get to tell them that they aren't going to school because of a similar threat on them," Westphal said.

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"I hate living with the fear that any given day, I could go to work one morning and return a widow and or (be) tasked with burying my kids, or both," Westphal said.

Westphal said that she would stay home with her kids Wednesday, and would pray for the safety of the teachers, administrators and staff. She said she was also grateful for Cady's level head.

"I will figure out how to be part of the solution. And the person(s) who is behind this, we heard your threat loud and clear. I will be very vocal in letting my opinion regarding your future be known," Westphal said.

The threat came the night before the National School Walkout planned for 10 a.m. Wednesday. Students across the Milwaukee region, including those from Pewaukee, were planning to walk out of classes to protest gun violence and call for gun control in the wake of the Feb. 14 shooting at Marjory Stoneman Douglas High School in Parkland, Florida, that killed 17.

Meanwhile, a rumor about a potential school shooting at Mukwonago High School during the walkout prompted the Mukwonago district to cancel student participation in the event, according to a post on the district's Facebook page.

Superintendent Shawn McNulty said the Mukwonago Police Department determined there was no validity to the rumor nor was there a credible threat to student safety. A parent alerted police about the threat, McNulty wrote in a letter to district families.

Reporter Steve Martinez contributed to this report.