Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. Obama, US Hold Moment of Silence for Shooting Victims VOA News 10 January 2011 A woman carrying âPeaceâ and âHopeâ signs arrives at a memorial outside the offices of congresswoman Gabrielle Giffords in Tucson, Arizona, 09 Jan 2011 Photo: Reuters A woman carrying âPeaceâ and âHopeâ signs arrives at a memorial outside the offices of congresswoman Gabrielle Giffords in Tucson, Arizona, 09 Jan 2011 U.S. President Barack Obama has led the nation in a moment of silence, to honor the victims of a mass shooting that killed six people and left a member of Congress critically wounded. The president and first lady Michelle Obama paused Monday at the White House, and staff and visitors gathered on the steps of the U.S. Capitol building to pay tribute to the victims of Saturday's attack in Tucson ((pron: TOO-sahn)), Arizona. The New York Stock Exchange and other public institutions also fell silent. The shooting happened as House Representative Gabrielle Giffords met with constituents outside a grocery store. Those killed included a federal judge, one of Giffords' aides, and a nine-year-old girl.  Speaking Monday in Abu Dhabi, U.S. Secretary of State Hillary Clinton called the shooter an "extremist" and described the 40-year-old Giffords as a "wonderful, incredibly brave young woman." The alleged gunman is to appear in a federal court in Phoenix ((Arizona)) on Monday. He faces one count of attempted assassination of a member of Congress, two counts of killing an employee of the federal government and two counts of attempting to kill a federal employee. The speaker of the House of Representatives, John Boehner, said that House votes scheduled for this week are postponed. Flags at the White House and other public and military buildings are to be flown at half-staff for the week.  Medical authorities on Sunday said they are "cautiously optimistic" about Giffords' recovery. Dr. Peter Rhee of Arizona's University Medical Center told reporters Giffords, who was shot in the head during the attack, is in a medically induced coma as she begins to recover from surgery. He said she has been following simple commands. Police say a woman waiting in line to meet Giffords grabbed the ammunition clip out of the shooter's hand as he paused to reload the gun. Two other bystanders then tackled the gunman, who was apprehended at the scene. Doctors said of the 14 people wounded, only Giffords remains in critical condition.  In several videos on the YouTube website, a person who posted under the name of the alleged shooter, 22-year-old Jared Loughner, criticizes the government and calls for a new currency. Law enforcement officials say they are investigating the videos. Last March, Giffords was one of at least 10 House Democrats harassed for their support of the U.S. health care reform legislation. The front door of her office in Tucson was shattered in an act of vandalism. In November, Giffords was re-elected to a third term in the House of Representatives. She was first elected to Congress in 2006. .