(WASHINGTON) -- In the wake of allegations of massive surveillance on foreign allies, leaders of the nation's top spy agencies told members of the House Intelligence Committee on Tuesday that their methods of protecting national security were not excessive and in fact, have prevented terrorist attacks both here and abroad since 2001.
Gen. Keith Alexander, whose National Security Agency has taken the brunt of the recent criticism, argued that more than a dozen terrorist strikes in the U.S. were stopped as well as 25 others in Europe.
Alexander said that was largely due to collecting phone calls and Internet exchanges overseas. He also denied reports in French, Spanish and Italian newspapers that the NSA mined the phone calls of tens of millions of their citizens.
He told lawmakers the data was actually collected by foreign partners and was information “that we and our NATO allies have collected in defense of our countries and in support of military operations.”
Alexander said the foreign media and their source, reportedly former NSA contractor Edward Snowden, “did not understand what they were looking at.”
Meanwhile, National Intelligence Director James Clapper discussed how the leaking of classified documents by Snowden was "extremely damaging to our ability to protect the country."
However, Clapper contended that the surveillance taking place overseas was not done arbitrarily but for valid reasons in the interest of national security.
As for tapping the phone conversations of foreign leaders, Clapper did not deny that was happening but added that U.S. allies have done the same with U.S. presidents.
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