A general view shows concrete barriers blocking the entrance of the U.S. embassy in Sanaa December 8, 2013. Yemen's Interior Ministry on Sunday announced it would heighten security and its readiness ... more 
A general view shows concrete barriers blocking the entrance of the U.S. embassy in Sanaa December 8, 2013. Yemen's Interior Ministry on Sunday announced it would heighten security and its readiness to confront any acts of terrorism that may target foreign embassies after Germany told its citizens to leave the country following Thursday's attack on Yemen's defence ministry that killed 52, including two German doctors. REUTERS/Mohamed al-Sayaghi (YEMEN - Tags: POLITICS MILITARY CIVIL UNREST) less 
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Reuters | Photo By MOHAMED AL-SAYAGHI / REUTERS
Sun, Dec 8, 2013 10:40 AM EST