One billion times last year passengers around the world boarded jets without their passports being checked with an Interpol system that tracks stolen or lost documents, officials have confirmed.

That fact contributes to the mystery of what happened to the Malaysian jetliner carrying 239 people that disappeared over the weekend on a flight to China.

After five days of searching, there is no solid evidence of what happened after two Iranian passengers used fraudulent passports to board Flight 370.

“Now, we have a real case where the world is speculating whether the stolen passport holders were terrorists, while Interpol is asking why only a handful of countries worldwide are taking care to make sure that persons possessing stolen passports are not boarding international flights,” said Interpol Secretary-General Ronal Noble, who is an American.

The two Iranian nationals who boarded Flight 370 were identified as Seyed Mohammed Reza Delavar and Pouria Nourmohammadii. They used authentic passports to travel to Kuala Lumpur, Malaysia, then obtained stolen Austrian and Italian passports to board the missing flight.

“While it is too soon to speculate about any connection between these stolen passports and the missing plane, it is clearly of great concern that any passenger was able to board an international flight using a stolen passport listed in Interpol’s databases,” Noble said.

The international police agency confirmed that in response to the jet’s disappearance, it will start giving access to its database to two airlines, Qatar Airways and Air Arabia. They were chosen because they asked.

However, access will be under controlled conditions established after the 9/11 attack. Indirect access to the database of the French-based Interpol will be through I-Checkit, which has been created for private sector companies.

At present, British and U.S. officials cross-check all passports with the database to ensure none is fraudulent.

However, most foreign governments and the airlines don’t bother.

The International Air Transport Association believes that even if airlines do have access to the Interpol database, they will be reluctant to check it.

“It is not a job for airlines,” said IATA Director General Tony Tyler. “It is up to governments to control borders. If there is a problem with border control and invalid passports, that is an issue which governments have to step up to and address.”

All that the airlines do, Tyler said, is a visual check of the names to see if they correspond with their passenger lists and the name on the individual’s passport.

“But that is as far as the responsibility goes,” Tyler said.

Interpol’s database has information on some 40 million stolen or lost passports to which national authorities and border police have had access.

Interpol gets some 60,000 hits from governments that use the Interpol database.

While 167 countries contribute information to the database, Interpol says that fewer than 20 of its member nations used the database systematically to check the validity of passports.

Just last month, Noble had issued a warning on the failure of countries to use the Interpol system. He that failure creates a “major gap in our global security apparatus that is left vulnerable to exploitation by criminals and terrorists.”

Generally, governments have not been willing to use the system, even though officials said it only takes a second for a country to query the Interpol database through software the agency provides.

Noble said that if Malaysia Airlines and all airlines worldwide were able to check the passport details of prospective passengers against the Interpol database, it would lessen any speculation.

But officials said governments that subject passengers to invasive security measures generally are unwilling to take the extra step to ensure the safety of the flight.

Sources argue that it may be better for airlines to provide the checks rather than governments. For one thing, airlines bear the cost to return passengers with stolen documents and it would be an incentive for them to do the checks.

Also, airlines are less constrained than governments by political and privacy concerns as well as limited resources to do the checks on the Interpol database.

“We are saying (that) because of the limitation of access by national authorities, then should we not consider providing access to the airlines themselves as well in a very controlled manner?” asked Michael O’Connell, who is director of Interpol’s operational police support directorate.

For that reason, Interpol will work with airlines through its I-Checkit’s indirect access to the Interpol database.

While incentives are being created for systematic passport checks, sources say there also is talk of providing financial assistance to countries with insufficient border-control resources to do the same.

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