[Update at 10:35 a.m.] The U.S. Capitol Police are preparing to transport the suspicious item into a specialized truck operated by the bomb squad, USCP spokeswoman Sgt. Kim Schneider told CNN.
The item will be transported with a Virginia State Police escort to Quantico, Virginia, where it will be rendered safe. FBI spokeswoman Lindsay Godwin said the item is being transported because it is dense and law enforcement authorities were having difficulty X-raying it.
Schneider said the area around the Capitol reflecting pool will remain closed until the scene is cleared.
[Posted at 7:56 a.m.] U.S. Capitol Police are responding to a suspicious object Thursday near the Capitol reflecting pool. Police told CNN the object is a pipe with wires and end caps.
This story is developing. We'll bring you more information as soon as we get it.