Firefighters and a hazardous materials response unit have been called to the scene
A woman was reportedly arrested after throwing something over the fence along Pennsylvania Avenue.
The street is often referred to as 'America's Main Street' and connects the White House and Capitol Hill in Washington D.C.
Firefighters and a hazardous materials response unit were called to the scene.
Today is Memorial Day in America. The lockdown began shortly after President Obama returned from making a speech at Arlington Cemetery.
The Secret Service stopped reporters from leaving the compound.