Heavy security grips U.S. capital for inauguration day

FBI special force members stand guard at the "We Are One"  welcome concert, attended by U.S. President-elect Barack  Obama and Vice President-elect Joe Biden and kicking off  the inauguration celebrations, at the Lincoln Memorial in  Washington D.C., the United States, Jan. 18, 2009.  (Xinhua/Hou Jun)

Starting from 3 p.m. Monday, security will be at its highest intensity and stay in place until 7 a.m. Wednesday, when major inaugural activities will be considered to have concluded.

Federal authorities said they have detected no credible and specific threats, but still they designated the inaugural as a National Special Security Event, giving the U.S. Secret Service the leading role in designing and implementing an overall security plan.

This plan, developed by the Secret Service in cooperation with over 50 local, state and federal security, public safety and military partners, includes road closures, security screenings, as well as additional air and water security measures.

As part of security enhancements, the military has deployed anti-aircraft missiles in scattered locations in the Washington area to deter and thwart any potentially disastrous attacks from the air.