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Good evening I'm -- green in red there.
The Obama administration's defense of NSA surveillance -- and usually public today on Capitol Hill.
The man in charge of electronic spying says more than fifty terror plots have been stopped -- intelligence correspondent Catherine Herridge has -- tonight.
Working with our allies.
Reading from a prepared statement the National Security Agency Director General Keith Alexander made a robust case that the sweeping data collection it's justified.
These programs together with other intelligence.
Have protected the US and our allies from terrorist threats across the globe.
To include helping prevent the terrorist the the potential terrorist events.
Over fifty times since 9/11.
On content whether it's email phone calls -- testing the NSA needs outside approval for American citizens is NSA spying today.
Or have you spied on American citizens.
But we we do not to target US persons anywhere in the world without a specific court warrant when it comes to sifting through the phone records of millions of Americans every decision is made internally.
Only twenty analyst at NSA and their two managers for total of 22 people are authorized to approve numbers that may be used to query this database.
As evidence the programs work.
Witnesses said in the disruption of a New York City Subway plot.
An attack on the New York Stock Exchange and overseas -- involving American David Headley who is tied to -- groups in Pakistan.
Asked whether phone records gathered under section 215 of the Patriot Act -- the only way to get the tips witnesses said it's more complicated than that -- really.
Hope you'll lose today for us.
Specifically case by case how many.
Stopped terrorist attacks where those programs to fifteen essential to do I think you ask it almost impossible question to say a how important each -- was.
Lawmakers were not told that US intelligence initially missed Headley who played a critical surveillance -- -- 2008 Mumbai terrorist attack.
For more than 400 people were killed and wounded nor -- witnesses explain that the -- stand of the New York subway -- -- relied heavily on British intelligence.
-- monitoring of a suspicious email account.
One lawmaker questioned whether the phone companies could hold the records rather than the US government.
I think jointly.
The FB IN SA are looking at the architectural framework of how we actually do this program Charlie -- -- us to vigorously investigate that.
And the number of potential plots in the US Alexander said only ten of the fifty he cited headed domestic connection.
Alexander added that the collection of foreign Internet communications.
Not domestic phone records accounts for most of the intelligence.
The disrupted attacks now the house and senate are considering bills to limit the NSA's data collection on American citizens change.
And more on that with the panel Catherine thank you welcome.
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