Exclusive | Inside the secret federal fraud unit youve never heard of, who take down billion-dollar crime syndicates

LARGO, MD — Everyday objects cluttered a cramped room, filling every surface and corner with what looks like discarded junk.It’s not a scene from the TV show “Hoarders.” Each piece in this little workshop is bugged—sometimes with cameras so small they’d fit through a pinhole.Above one heap, a wall-mounted television displays a grid of live feeds from a dozen surveillance cameras across the nation — one fixed on a house in California, another an apartment complex in Ohio, a third showing a storefront in Manhattan.“A lot of what we’re doing is proving a negative,” one federal agent said as he worked on placing a tiny camera into an object.He points to a feed of a stately home on a cul-de-sac.

“This doctor in California is billing for seeing patients right now.That’s his car in the driveway.

He’s actually at home.”The Knock, as they call it, short for National Training Operations Center (NTOC), is the high-tech crimefighting headquarters for a branch of law enforcement many people don’t know exists—the Department of Health and Human Services Office of Inspector General (HHS-OIG).HHS-OIG is the primary investigative agency behind many splashy fraud takedowns in recent months, including a $10 billion urinary catheter scheme linked to the Russian mob and an alleged $38M adult day care scam busted in Brooklyn, which ensnared Pakistani community leaders who cozied up to top Democrats.Investigators admit it’s an unsexy job—chipping away at the nation’s explosive healthcare fraud epidemic—but someone’s got to do it, even if they never seem to get much credit.Luckily, The Post got an exclusive tour of The Knock, an elite facility tucked away in a leafy, suburban medical plaza outside Washington, DC.Behind blacked-out plate windows and an unmarked storefront, a small army of data analysts, digital forensics investigators and good ol’ fashion shoe leather cops work to claw back billions of dollars stolen from taxpayers each year...