Security in Washington, D.C. will be understandably tight today. Officials say there will be as many as 25,000 police officers, security agents and National Guard troops on duty. That includes snipers and undercover agents mingling in the crowds. The secret service has closed down wide areas of the city around the White House and U.S. Capitol building. Much of it will be off limits to any unauthorized vehicles. Bridges over the Potomac River have also be closed. And just so that nothing is missed 100 agents will be watching footage from surveillance cameras: 5,265 cameras to be exact.