Washington, July 9 (ANI): An investigative arm of the US Congress has revealed that bomb parts were sneaked past guards and assembled inside several US government buildings by undercover agents.

The Government Accountability Office (GAO) report revealed that these undercover agents carried liquid explosives and detonators, and were able to pass undetected through security checkpoints at 10 buildings in the past year.

The report also said that the officials assembled the bombs and walked freely around the premises with the devices in a briefcase, Sky News reports.

Though, GAO did not provide specific information citing security concerns, it said that "level 4" buildings were randomly selected, which house more than 450 federal employees.

Several buildings including the office of a US senator as well as the departments of state, justice, and homeland security were tested.

Meanwhile, numerous leaders were startled over the shocking security lapses at such high level buildings in the country.

"It is simply unacceptable that federal employees working within buildings under FPS' protection, and the visitors who pass through them, are so utterly exposed to potential attack by terrorists and other enemies," said independent senator Joseph Lieberman.

While, Republican senator Susan Collins articulated the security lapses as stunning and unacceptable, saying that: "In post-9/11 America, I cannot fathom how security breaches of this magnitude were allowed to occur."

According to reports, more than one million US government employees work at 9,000 FPS-protected sites around the country, including 350,000 in and around Washington DC. (ANI)