WASHINGTON-Here’s a friendly reminder from the Pentagon police chief: please fill out the proper forms before you bring a bomb to work. The advice came after security guards at the Defense Department’s entrance discovered parts of a disabled homemade bomb on a civilian entering the building last month, officials said.

The incident may have set off alarm bells at other government offices but police at the sprawling headquarters for the US military are accustomed to unusual items carried in by employees. In this case the civilian had brought in the disarmed improvised explosive device (IED) to brief senior naval officers on roadside bombs - the number one killer of American troops over the past decade. “He had inert components of an IED, basically wires and switches,” said Pentagon spokesman Lieutenant Colonel Tom Crosson.

But there was “nothing explosive,” he told AFP. The civilian, employed by the US Navy, had failed to secure written permission before showing up on November 19. After some phone calls and checks, he was eventually let in with the bomb parts, Crosson said.

Steven Calvery, head of the Pentagon Force Protection Agency, which handles security for the giant office building in Arlington, Virginia, has since asked employees to brush up on procedures for bringing in inoperable guns or disarmed explosives.