A U.S. congresswoman was critically injured Saturday after a shooting in her district in the southwestern state of Arizona that killed several others, including a federal judge and a 9-year-old girl.
Democratic Representative Gabrielle Giffords was shot in the head, one of as many as 18 people hit outside a grocery store in the city of Tucson.
President Barack Obama, speaking from the White House late in the day, called the shooting an "unspeakable tragedy" and said the director of the Federal Bureau of Investigation, Robert Mueller, is on his way to Arizona to coordinate the probe into the attack.
The director of trauma surgery at the University of Arizona hospital, where Giffords was taken, Dr. Peter Rhee, said he is optimistic about her recovery.
Dr. Rhee said the hospital received 10 victims total, including five in critical condition and the child who died.
The 40-year-old Giffords had been meeting with constituents at the grocery store.
Police say the shooter is in custody. He has been identified by people familiar with the investigation as Jared Loughner, a 22-year-old male.
In several YouTube videos, a person who posted under the name Jared Loughner criticizes the government and calls for a new currency. Law enforcement officials say they are investigating the videos.
Arizona Governor, Republican Jan Brewer, said all of Arizona is shocked and deeply saddened by the incident. House Speaker John Boehner said he is horrified by the attack, calling it "senseless."
Tucson is in southern Arizona, about 130 kilometers from the Mexican border.
In November, Giffords was re-elected to a third term in the House of Representatives. She was first elected to Congress in 2006.
U.S. Capitol police responded to the shooting by advising lawmakers and their staff to "take reasonable and prudent precautions regarding their personal security."