A federal employee was arrested for allegedly spreading a false active shooter threat at Joint Base McGuire-Dix-Lakehurst in New Jersey, triggering a morning lockdown.

The lockdown, which affected over 42,000 personnel across one of the nation’s largest military installations, was lifted within an hour.

Acting U.S. Attorney Alina Habba condemned the “senseless fear-mongering” and pledged legal action, the Associated Press has reported.

The incident occurred amid heightened attention to military base security following recent shootings at U.S. installations.