Photo: AP

Earlier this month, Jonathan Wienke, an analyst in the Department of Homeland Security’s Office of Intelligence and Analysis, was arrested after carrying a gun, a knife, an infrared camera, pepper spray, and handcuffs into the agency’s headquarters. Now, court filings show, federal prosecutors are investigating whether Wienke was planning an attack on senior DHS officials.

Wienke pleaded not guilty to a gun charge after his initial arrest, NBC Washington reports. However, prosecutors say they have probably cause to believe that the analyst “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.”

The senior officials were meeting not far from Wienke’s workspace on the day of his arrest. Wienke, who had top-secret clearance, was aware of the meeting.

In an affidavit for a search warrant to enter Wienke’s house, DHS special agent Eric Mann described what happened the day Wienke was arrested. The Associated Press reports:

At 7.30am on 9 June Wienke entered the building, which has a security level on par with the White House and the Pentagon, according to Mann’s affidavit. Security measures include random screening at the door; Wienke was selected and his backpack was placed in a screening machine.

Security officers found a folding knife with a three-inch blade, two handheld radios, pepper spray, an infrared camera and a set of handcuffs, among other items, the affidavit states. The officers seized the knife and spray.

At 9am Mann and another officer followed up with Wienke at his cubicle, directly across from where senior officials were meeting, the documents say.

He gave them permission to search him and denied he was carrying any additional weapons, the affidavit alleges. Mann wrote that he patted Wienke down and discovered a five-shot revolver loaded with .22-caliber hollow-point rounds in the front pocket of his pants. He wrote that he heard Wienke “utter an audible expletive”.

According to a DHS spokesperson, Wienke has been placed on administrative leave.