DHS Internal Watchdog 'Deeply Concerned' Over TSA's Screening at Airports

Poor detection rates set off alarms inside the agency.

“We believe there are vulnerabilities in TSA’s screening operations, caused by a combination of technology failures and human error,” DHS Inspector General John Roth told a Senate hearing today. “TSA cannot afford to miss a single, genuine threat without potentially catastrophic consequences.”

But a top TSA official at Minneapolis-St. Paul International Airport blamed much of the problem on "poor morale," saying a survey of government workers last year found her agency's workforce had some of the lowest morale in the entire federal government.

Rebecca Roering, TSA's assistant federal security director at the Minneapolis airport, said the poor detection rates reported by ABC News last week “cause great concern.”

At the same time, Johnson and others at today’s hearing noted the difficult work of TSA’s 50,000 officers, who screen nearly 2 million passengers and 3 million carry-on bags each day.

They have “an enormous challenge,” Johnson said.

Still, according to officials briefed on the results of the inspector general’s investigation, TSA officers failed 67 out of 70 tests, with so-called “Red Team” members repeatedly able to get potential weapons through checkpoints.

In one test, an undercover agent was stopped after setting off an alarm at a magnetometer, but TSA screeners failed to detect a fake explosive device that was taped to his back during a follow-on pat down.

Officials would not divulge the exact time period of the testing, other than to say it concluded recently.

Homeland Security Secretary Jeh Johnson was apparently so frustrated by the findings he sought a detailed briefing two weeks ago at TSA headquarters in Arlington, Virginia, according to sources. U.S. officials insisted changes have already been made at airports to address vulnerabilities identified by the latest tests.

“Upon learning the initial findings of the Office of Inspector General's report, Secretary Johnson immediately directed TSA to implement a series of actions, several of which are now in place, to address the issues raised in the report,” the DHS said in a written statement to ABC News.

Homeland security officials say that security at the nation’s airports is strong; that there are layers of security including bomb sniffing dogs and other technologies seen and unseen.

This is not the first time the TSA has had trouble spotting Red Team agents. A similar episode played out in 2013, when an undercover investigator with a fake bomb hidden on his body passed through a metal detector, went through a pat-down at New Jersey's Newark Liberty Airport, and was never caught.

At the time, the TSA said Red Team tests occurred weekly all over the United States and were meant to “push the boundaries of our people, processes, and technology.”

“We know that the adversary innovates and we have to push ourselves to capacity in order to remain one step ahead,” a TSA official wrote on the agency’s blog in March 2013. “[O]ur testers often make these covert tests as difficult as possible.”

“[Testers] know exactly what our protocols are. They can create and devise and conceal items that … not even the best terrorists would be able to do,” Pistole told lawmakers at a House hearing.

At today’s hearing, DHS Inspector General Roth also raised concerns over TSA’s ability to vet aviation workers granted access to sensitive areas at U.S. airports.

More recently, Roth’s office concluded a series of undercover tests targeting checked baggage screening at airports across the country.

That review found “vulnerabilities” throughout the system, attributing them to human error and technological failures, according to a three-paragraph summary of the review released in September.

In addition, the review determined that despite spending $540 million for checked baggage screening equipment and another $11 million for training since a previous review in 2009, the TSA failed to make any noticeable improvements in that time.

TSA has an annual budget topping $7 billion.

ABC News’ Pierre Thomas, Jack Date and David Kerley contributed to this report.