According to News4 in Washington, D.C., federal agents are investigating an employee who was possibly plotting an attack on senior DHS officials earlier this month from his workspace within the U.S. Department of Homeland Security.

Investigative reporter Scott MacFarlane reports that Jonathan Wienke of Martinsburg, W.Va., was selected for a random security screening while arriving for work on the same day that a meeting of senior agency officials was scheduled near his workspace. That search turned up a knife, pepper spray, thermal imaging equipment, and radio devices, which security officers seized before allowing Wienke to proceed.

MacFarlane reports that a second screening conducted before the meeting turned up a gun loaded with hollow-point bullets.

A federal agent said in a court filing that there was “probable cause to believe Jonathan Wienke was conspiring with another to commit workplace violence, and more particularly may have been conspiring or planning to commit violence against the senior DHS officials in the building.”

Wienke has pleaded not guilty to a gun charge.