There appears to have been a serious security breach in the United States with a confidential airport security manual being posted on the internet.
The 90 page manual was marked "Sensitive Security Information." It's apparently been on the internet since March.
The passenger screening procedures offer an insight into how to avoid security.
The document includes details on the appearance of CIA and Air Marshalls' ID cards and technical information about security checks.
While officials have acknowledged the blunder, they insist the manual is out of date and that travellers have not been put at risk.
