A leaked manual on security measures at US airports reveals that Lebanese passport-holders are made to go through tighter screening when traveling to America.

Lebanese citizens will automatically be subject to greater security checks at the airport “unless there are specific instructions not to,” according to the secret Homeland Security document.

Extra screening measures could include being asked to remove footwear, body scanning by airport staff, lengthier questioning at passport control or an increase of hand luggage checks.

The document, marked as “sensitive security information,” is the first to let slip post-9/11 security details for American airports and reveals that travelers from certain countries are treated with greater caution.

Lebanon is one of a dozen singled out on the list, along with Cuba, Iran, North Korea, Libya, Syria, Sudan, Afghanistan, Somalia, Iraq, Yemen, and Algeria- all countries the US has experienced strained diplomatic relations with in the last few years.

Senator Susan Collins, a ranking member of the Senate Homeland Security Committee, called the release of the information shocking and reckless this week, saying the manual “provides a road map to those who would do us harm.”

Security at US airports has been significantly tightened since the September 11, 2001 attacks when hijackers commandeered four commercial planes, crashing them into the World Trade Center and the Pentagon.

Passengers are now more likely to experience being patted-down or thoroughly checked by screeners using hand-held metal detectors as part of a new policy adopted after the attacks.