US shootings: 'Cautious optimism' over Giffords

• People bow their heads during a prayer service for those killed or wounded during the attack. Picture: Getty

The rampage in Tucson on Saturday fuelled debate about extreme political rhetoric in America after an acrimonious campaign for congressional elections last November.

The 22-year-old suspect was formally charged in federal court yesterday as investigators sought a motive.

"It appears that the target was the congresswoman," FBI Director Robert Mueller told a news conference yesterday.

He said public officials should be on alert but there was no information to suggest a specific threat against them.

Doctors said Ms Giffords, a 40-year-old Democratic politician, was in critical condition but was able to follow simple commands, such as holding up two fingers when asked. A single bullet travelled the length of her brain on the left side.

But given the devastating nature of the wound, doctors at University Medical Centre in Tucson said they were uncertain about the extent of brain damage she had suffered.

The bullet hit an area of the brain that controls speech functions and the wound will lead to some degeneration of brain cells, they said. Giffords has been put into a pharmaceutical coma but was being woken frequently to check her progress.

They credited several reasons for her survival, including good luck and the fact that paramedics got her to surgeons quickly - in under 40 minutes - with the help of a helicopter.

"This is about as good as it is going to get," said Dr Peter Rhee, a trauma surgeon. "When you get shot in the head and the bullet goes through your brain, the chances of you living is very small and the chances of you waking up and actually following commands is even much smaller than that."

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The suspect, identified as Jared Lee Loughner, opened fire with a semi-automatic pistol at point-blank range outside a Safeways supermarket, killing six people including US federal judge John Roll and nine-year-old Christina Green. Fourteen people were wounded.

The violence shocked politicians in Washington, where Congress postponed a vote on healthcare reform later this week. Some Democrats were quick to say a shrill climate of political vitriol might have played a role.

Mourners crammed into the tiny sanctuary of Giffords' synagogue in Tucson yesterday to pray for her quick recovery. Outside the hospital, candles flickered at a makeshift memorial.

Signs read "Peace + love are stronger," "God bless America and "We love you, Gabrielle." People also laid down bouquets of flowers, American flags and pictures of Giffords.

Mr Mueller, who was sent by US Attorney General Eric Holder to Arizona to help co-ordinate the investigation, said Loughner bought the Glock 9-mm handgun used in Saturday's shooting last year.

In one of several YouTube videos, which featured text against a dark background, Loughner described inventing a new US currency and complained about the illiteracy rate among people living in Giffords' congressional district in Arizona.

"I know who's listening: Government officials, and the people," Loughner wrote.

"Nearly all the people, who don't know this accurate information of a new currency, aren't aware of mind control and brainwash methods."Neighbours in Loughner's middle-class neighbourhood - about a five-minute drive from the scene - said he lived with his parents and kept to himself. He was often seen walking his dog, almost always wearing a hooded sweat shirt and listening to his iPod.

He was described by friends as a pot-smoking loner who was rejected by the US Army when he tried to enlist in 2008. He dropped out of a local community college after having five contacts with campus police for classroom and library disruptions last year.