An undercover TSA inspector with a fake bomb stashed in his pants passed through a metal detector and a pat down and was cleared to board a commercial flight at New Jersey's Newark Liberty Airport.

The Transportation Security Administration told ABC News that the exercise was one of the "red team" tests that take place across the country each week.

"It’s sort of like a red teaming scenario," Frank Cilluffo of the Homeland Security Policy Institute told ABC.

"You intentionally look for where the weak point is in the system. I think it clearly identified a vulnerability."

Sources told the New York Post that the agent was part of a four-person "red team" that posed as ticketed passengers and went through the B1 checkpoint of Terminal B — home of American Airlines, JetBlue and Delta.

The "bomber" got through the metal detector around 11am, was pulled aside for a pat down and then was allowed to go to his gate.

"He did have a simulated IED in his pants," the source told the Post. "They did not find it."

It is not clear how large the inert "bomb" was or what materials it was made with.

New York Congressman Peter King is calling for an extensive review over the Feb 25 incident.

"The fact that 11½ years after 9/11 you’re able to get explosives past security onto a plane is absolutely inexcusable; it’s disgraceful," Rep. King (R-N.Y.) told The New Jersey Star-Ledger in a telephone interview.

"Over the years, there’s been a number of security breaches at Newark airport … such as people being at areas of the airport where they’re not allowed to be."