Associated Press - July 8, 2009 8:23 PM ET

SIOUX FALLS, S.D. (AP) - Environmentalists who hung a banner on Mount Rushmore National Memorial calling for a stop to global warming have been arrested.

A federal prosecutor says 11 people pleaded not guilty to trespassing and the misdemeanor crime of climbing on Mount Rushmore.

The environmental group Greenpeace says in a statement that its members hung the 2,300-square-foot banner that read, "America honors leaders not politicians: Stop Global Warming."

The banner was removed about an hour after it was unfurled from the top of the mountain Wednesday and hung alongside the carving of former President Abraham Lincoln.

Greenpeace says the activists scaled the monument using rock anchors used by the National Park Service. A park ranger says tourists helped alert park officials.

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