Library of Congress evacuated after alarm goes off Tuesday night

The historic main building of the Library of Congress was evacuated for a time Tuesday night, the U.S. Capitol Police said.

A water alarm went off in the Jefferson building, said Lt. Kimberly Schneider. Parts of First Street and East Capitol Street were blocked off as emergency vehicles responded.

epa04176175 Shane Red Hawk of the Sicangu Lakota band of the Rosebud Sioux (L) and his daughter Tshina Red Hawk (R) wait for tribal leaders with the 'Cowboy and Indian Alliance' to begin a horseback ride in protest of the Keystone XL Pipeline across from the National Museum of the American Indian in Washington, DC, USA, 22 April 2014. The alliance of farmers, ranchers, and tribes has dubbed their week-long series of protests 'Reject and Protect.' EPA/JIM LO SCALZO

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The evacuation was carried out as a precaution, but an all clear was given after about an hour or two, authorities said.

It was not immediately clear what had triggered the alarm. No information was available immediately about the extent of any damage in the building. In addition to a large book collection, it houses artistic, historic and cultural treasures.

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