Campus Alert Archive
U-Mary

A Yik Yak Pipe-Bomb Post Triggers a 100-Minute Shelter-in-Place at a Catholic University

NDbomb threatemergency notificationmedium confidence
Confirmed HoaxDetermined to be a hoax. The institutional response is documented because it reveals how the alert system performed under a perceived real threat.

On Friday, February 17, 2023, the University of Mary near Bismarck, North Dakota, ordered a shelter-in-place after a threat to plant pipe bombs in a campus bathroom. The threat originated in an anonymous Yik Yak post the night before that the app intercepted and reported. The Burleigh County Sheriff's Department issued the shelter order about 12:50 p.m. and arrested 19-year-old Chase Hoechst shortly after 1:30 p.m.; no explosive devices were found. Hoechst was charged with felony terrorizing and later sentenced to probation and community service on a reduced charge.

Alerts
2
Response
—
Killed
0
Injured
0
Institution
University of Mary
Private Masters · ND
~4,000 studentsU-Mary Emergency Alert
Confirmed Timeline

Alert Sequence

2 messages in sequence

Some alert texts below are approximate reconstructions from news coverage, not confirmed verbatim transcripts. Reconstructed texts are shown in italic with a dashed border. Verified verbatim texts have a solid border and are marked accordingly.

INITIAL ALERTSMS
Approximate reconstruction213 chars
U-Mary Emergency Alert: SHELTER IN PLACE. Law enforcement is responding to a threat on campus. Lock or barricade doors, stay away from windows, and remain in place until further notice. Do not leave your location.

This text has been reconstructed from news coverage and may not reflect the exact original wording.

Reconstructed paraphrase; isVerbatimConfirmed is false because the exact U-Mary alert text could not be confirmed.
The Bismarck Tribune reported deputies responded at 11:30 a.m. and the shelter-in-place was issued about 12:50 p.m. CST, after the FBI relayed the intercepted threat.
North Dakota observes Central Time; in February the region is on CST, so the order went out around 12:50 p.m. CST.
ALL CLEARSMS
Approximate reconstruction176 chars
U-Mary Emergency Alert: The shelter in place is lifted. A suspect is in custody and a search found no devices. There is no further threat to campus. Normal activity may resume.

This text has been reconstructed from news coverage and may not reflect the exact original wording.

Reconstructed paraphrase; isVerbatimConfirmed is false because the official lift message text was not available.
This is a genuine all-clear: it lifts the shelter-in-place after the arrest and a sweep that found no devices, and states there is no further threat.
The shelter-in-place lasted about an hour and 40 minutes, bracketed by the ~12:50 p.m. order and the arrest of Chase Hoechst shortly after 1:30 p.m. CST.
Context

Background

The University of Mary is a private Catholic, Benedictine university of about 4,000 students just south of Bismarck, North Dakota. On Friday, February 17, 2023, it experienced a bomb-threat shelter-in-place that began with social media. According to the Bismarck Tribune, 19-year-old Chase Hoechst posted around 6:30 p.m. the previous evening on Yik Yak that he had 'planted pipe bombs in the caf bathrooms'; the app intercepted the message and reported it, and the FBI notified the Burleigh County Sheriff's Department around midday Friday. KFYR-TV reported deputies responded at 11:30 a.m. and a shelter-in-place was issued about 12:50 p.m. CST; Hoechst was arrested shortly after 1:30 p.m. and no devices were found. He was charged with felony terrorizing, and the Bismarck Tribune later reported he pleaded to misdemeanor reckless endangerment and received about a year of unsupervised probation and 100 hours of community service. The case is a clear example of anonymous-app threats — a recurring driver of campus shelter-in-place orders — being intercepted by the platform itself and routed to law enforcement.
Analysis

Key Findings

An anonymous Yik Yak pipe-bomb post — intercepted by the app and reported — drove a real-world shelter-in-place at a private Catholic university
The shelter-in-place lasted roughly 100 minutes, from the ~12:50 p.m. CST order to the arrest shortly after 1:30 p.m.
A swift arrest of 19-year-old Chase Hoechst and a no-device sweep allowed a prompt all-clear
The felony terrorizing charge was later reduced to misdemeanor reckless endangerment with probation, a common outcome for non-credible campus threats by young first offenders
Outcome
No explosive devices were found during the campus sweep. The shelter-in-place lasted about an hour and 40 minutes. Chase Hoechst, 19, of Bismarck, was arrested and charged with felony terrorizing; he later pleaded to misdemeanor reckless endangerment and received probation and 100 hours of community service.
Provenance

Sources

  1. News
    U-Mary bomb threat brings terrorizing charge - Bismarck Tribune
    bismarcktribune.com
  2. News
    UPDATE: Man arrested in threat to University of Mary Campus - KFYR-TV
    kfyrtv.com
  3. News
    Person of interest apprehended at UMary for bomb threat - KX Net
    kxnet.com
  4. News
    Former U-Mary student gets probation, community service for February bomb threat - Bismarck Tribune
    bismarcktribune.com
Tags
bomb-threatshelter-in-placeyik-yaknorth-dakotaemergency-notificationcatholic-universityu-maryHoax
Added May 2026Updated May 2026Via ingestion