Bedouins watch flames rise in July 2011 after masked gunmen blew up a terminal of the Egyptian natural gas pipeline to Israel and Jordan. It was one of many attacks on the pipeline since the popular uprising that ousted longtime Egyptian leader Hosni Mubarak last year. AP hide caption

itoggle caption AP

Egyptian soldiers stand guard in front of the U.S. National Democratic Institute, an NGO rights group in downtown Cairo on December 29, 2011. Filippo Monteforte/AFP/Getty Images hide caption

itoggle caption Filippo Monteforte/AFP/Getty Images

In Cairo earlier today, a masked Egyptian protester prepared to throw back a tear gas canister fired by security forces. Mahmud Hams/AFP/Getty Images hide caption

itoggle caption Mahmud Hams/AFP/Getty Images