Bomb-making materials were smuggled into key US government buildings on 10 occasions last year, a congressional report has revealed.
The Government Accountability Office said that undercover investigators infiltrated buildings included the offices of a senator and a congressman.
Once inside, undercover investigators were able to assemble bombs and carry them
around freely.
The BBC reported that the congressional report cited instances of guards falling asleep on the job or failing to detect explosives at X-ray scanners. The US spends around $1 billion a year protecting thousands of government buildings across the country which are guarded by an army of 13,000 contract security workers.
The BBC reported that the report flagged up an incident where one guard accidently fired his gun into a mirror in a public lavatory while practicing pulling it out of its holster.
On another occasion, a baby was sent through an X-ray machine.
Senate Homeland Security Committee chairman, Senator Joe Lieberman, said the failings were "simply unacceptable".
