The newest top-secret listening devices currently used by the world's most advanced spy agencies are most likely something that even many experts have never seen.
"If I know about it, they're not using it," Fischer said.
This complicates the work of the FBI agents in plainclothes who watch over their building site, which sits across McCarter Highway from the New Jersey Performing Arts Center.
But the background checks have weeded some potential workers from the site.
A number of people have been rejected," said Evanina, who is the FBI project manager overseeing the Newark headquarters building.
One person involved in the construction said that "there are a lot of people who applied [to work on the tower] who had dual citizenship" and were rejected.
The complex, which will also house ground-floor restaurants facing the riverbank esplanade now under construction, was designed to withstand bomb blasts. But it was rendered architecturally so that it complements its Performing Arts Center neighbor across the street.
"It's going to look like a professional office building," Evanina said.
Agents are scheduled to move there in November; the building will double the agency's space from its existing offices inside the Gateway Center.
Monica Holden, a health-care worker who recently spent her lunch hour reading on a bench on the Performing Arts Center grounds, said the FBI building and its planned river walk would be a welcome development to efforts to revitalize the city's downtown. But she said the notion that foreign spies might try to watch the comings and goings of FBI agents from an esplanade restaurant seemed unsettling.
"It will be something in the back of your mind," Holden said. "The fact that we don't even know who they are makes it even worse."