A US House Representative, Gabrielle Giffords, is battling for life after a gunman shot her in the head at a political event in Arizona Saturday morning and then turned on others killing six including a nine-year-old girl.
Giffords, a Democrat, was meeting constituents at a "Congress at your corner" event near a grocery chain store Safeway when the gunman identified by the authorities as Jared Lee Loughner opened fire.
Loughner, 22, has been taken into custody and investigations are underway, coordinated at the highest level by FBI director Robert Mueller from the crime area on President Barrack Obama's instructions.
"This is more than a tragedy for those involved," Obama said in a statement on the shooting, adding, "It is a tragedy for Arizona and a tragedy for our entire country."
House Speaker John Boehner, of the Republican Party, called it "a sad day for the country."
He added, "An attack on one who serves is an attack on all who serve."
A federal Judge John M Roll, who had earlier received death threats for his rulings on immigration cases, is among the six dead.
The others, including Giffords, 40, were being treated at a local hospital. The representative was, in fact, declared dead in initial reports. But doctors later said they were optimistic of her chances of surviving.
Not much is known about Loughner. The authorities have only identified him as a 22 year local man, with a possible Army history. In a video apparently posted by him on YouTube he describes himself as a "conscience dreamer".
His social network webpage listed Hitler's Mein Kampf and the Communist Manifesto among his favoured readings. But none of this is confirmed, most of this sourced to crazed internet digging underway since the incident.
Giffords is described as a Blue Dog Democrat, a conservative Democrat, who narrowly defeated her Tea Party rival to keep her seat in the face of a resurgent Republican Party.
While there was no word yet on the motive of the assailant, commentators speculated if it her shooting had anything to do with her politics - she was a bitter critic of Arizona's tough anti-immigration law.
But like most people in her state, Giffords was a staunch supporter of the rights to posession weapons. The police said the weapon used by Loughner - a Glock 19 pistol - was bought by him legally at in November.