The Federal Bureau of Investigation and local police are investigating a shooting near Tucson, Ariz., that critically injured US Rep. Gabrielle Giffords (D) and left an aide, a 9-year-old child, a federal judge, and at least two others dead, law-enforcement officials say.
The shooting occurred shortly after 10 a.m. local time Saturday as the Arizona lawmaker was holding an outdoor meeting with constituents at a Safeway supermarket. It was billed as her first "Congress on Your Corner" meeting for 2011.
The attack, which injured at least a dozen other people, involved an automatic weapon, according to the Associated Press. Little is known about the suspect, who is in police custody.
Among those killed was US District Judge John Roll. He joined the federal court in 1991, and for part of his tenure, he had served as chief judge.
Although some early accounts had the congresswoman among the fatally wounded, the Associated Press reports that doctors at the hospital where she was taken say that they are "optimistic" and that she was responding to doctors' instructions.
Reaction from Washington to the Arizona shooting was swift.
President Obama called the attack "an unspeakable tragedy ... a senseless and terrible act of violence that has no place in a free society."
During a brief statement Saturday afternoon, Mr. Obama said he had sent FBI Director Robert Mueller to Arizona to coordinate the investigation into the attack.
House Speaker John Boehner (R) of Ohio said in a statement, “I am horrified by the senseless attack on Congresswoman Gabrielle Giffords and members of her staff. An attack on one who serves is an attack on all who serve.... This is a sad day for our country."
House minority leader Nancy Pelosi added in a statement, "This terrible act of violence is a national tragedy.... It is especially tragic that she was attacked as she was meeting with her constituents whom she serves with such dedication and distinction."
Voters first sent Giffords, a onetime Republican, to Congress in 2006.
In the last session of Congress, when Democrats were in power, she headed the House Science Committee's Subcommittee on Space and Aeronautics. She has been an outspoken skeptic of Obama's new direction for the National Aeronautics and Space Administration.
Following Giffords's vote in favor of Obama's health-care reform package, the lawmaker's Tucson office was vandalized. The attack was widely seen as part of a broader backlash by more-radical elements of the tea party against lawmakers who back the health-care overhaul.