Report Reveals Huge Air Cargo Security Hole

There is a gaping hole in aviation security, a hole so big about one billion pounds of cargo fly right through it every year -- cargo on passenger planes coming into this country that never gets inspected, reports CBS News investigative correspondent Armen Keteyian .

"To the extent it's not screened, we believe that represents a potential vulnerability," Stephen Lord, director at the Government Accountability Office told CBS News.

Lord authored a revealing report on air cargo security released in June. In it:

-He found "a significant percentage" of inbound cargo on passenger planes is "not required" to be screened.

-The report also noted: There remains "no technology approved" to screen large pellets and containers in a way that meets federal standards.

-And while the TSA estimates 65 percent of inbound cargo is screened, the report found that estimates "are not based on actual data".

"We found some data reliability problems, so we didn't have a lot of confidence in their numbers," said Lord.

In March a TSA administrator told Congress that the agency has a long way to go.

Now it says it could be as late as 2013 before all cargo on international passenger planes is screened.

One reason: The air cargo industry has resisted 100 percent inspection. Arguing, in these letters to Congress, obtained by CBS News, that screening must be "accomplished in a manner that allows for the free flow of commerce."

Congressman Edward Markey says that argument no longer flies.

"We can no longer allow the cargo industry to block the implementation of strong, tough measures that prevent al Qaeda from exploiting, once again, the weaknesses in our security in aviation," said Rep. Markey.

While these additional screening steps undoubtedly help, the fact remains it wasn't screening that found these latest bombs - it was a tip.