Congresswoman Gabrielle Giffords making progress

In yet another sign of significant recovery during a remarkable week, the gravely wounded US Representative Gabrielle Giffords was upgraded from critical to serious condition after a procedure to remove her from a ventilator was successful.

Doctors have been positive, and at time almost giddy, in describing her progress since she was shot point blank in the head on January 8.

Ms Giffords responded from the moment she arrived at the emergency room, at first just squeezing a doctor's hand.

Then she raised two fingers. She opened her unbandaged eye shortly after President Barack Obama's bedside visit on Wednesday.

Then, more milestones - which doctors said were all indicative of higher cognitive function - were achieved, all with her husband, astronaut Mark Kelly, at her side.

Mr Kelly asked her to give him a thumbs-up if she could hear him. She did more than that. She slowly raised her left arm. By the end of the week, she had moved her legs and arms.

At the hospital, more than 100 people were gathered amid the sea of get-well balloons and cards when the University of Arizona put out a statement upgrading her condition.

As night fell, candles at the makeshift memorial began to flicker. A mariachi band played the The Star-Spangled Banner.

Doctors decided to upgrade her condition because the tracheotomy done a day earlier was uneventful, hospital spokeswoman Katie Riley said.

A feeding tube was also put in on Saturday, and doctors speculated that they might soon know if she could speak.

Few people survive a bullet to the brain - just 10% - and some who do end up in a vegetative state.

It is even more rare for people with gunshot wounds to the head to regain all of their abilities, and doctors have cautioned that the full extent of Ms Giffords' recovery remains uncertain.

Ms Giffords and 18 others were shot when a gunman opened fire at a meet-and-greet she was hosting outside a supermarket in her own hometown. Six people died.

Meanwhile, a week after the Tucson supermarket massacre, more details emerged about a shooting victim who police said became distraught and was arrested during a televised town hall meeting.

James Eric Fuller, a self-described liberal and military veteran, started ranting at the end of the programme on Saturday.

He took a picture of a local tea party leader and yelled "you're dead" before calling others in the church a bunch of "whores", authorities said.

Deputies called a doctor and decided he should be taken to a hospital for a mental evaluation, said Pima County sheriff's spokesman Jason Ogan said.

In media interviews and on the internet, Mr Fuller, a former limousine driver and Census worker, has said he worked hard to get Ms Giffords re-elected in her conservative-leaning district.

He was going over questions he had prepared for the congresswoman, when the shooting began, he said in an interview with the television show Democracy Now.

He was shot in the knee and back and drove himself to the hospital, where he spent two days.

"I didn't know how to calm myself down," he said on the TV show, "so I wrote down the Declaration of Independence, which I memorised some time ago. And that did help to organise my thoughts."

He also lashed out at conservative Republicans for "Second Amendment activism", arguing it set the stage for the shooting.

Mr Fuller returned to the Safeway supermarket on Friday, telling KPHO-TV he had always considered trauma a figment of imagination until the events of January 8.

"Today I'm back on my feet, more or less, and I'm in a combative mood," Mr Fuller said as he limped across the store parking lot. "It's helping me. I've never had any trauma like this in my life."

Later, he showed up at the home of accused gunman Jared Loughner, who lived within a half-mile of Mr Fuller.

"He said he was going to forgive him for shooting him," Richard Elder, 86, a retired medical mechanic who lives next door to Mr Fuller, said.

Mr Fuller posted about eight campaign signs in front of his house during the last election, including one for Ms Giffords. And although Mr Fuller was friendly, he acted odd sometimes, Mr Elder said. Once, Mr Fuller asked him if he was going to vote.

"I told him there are two things I don't talk about: politics or religion. I told him that, and he walked off without another word."

He said Mr Fuller had shown him his bullet wounds and seemed to be dealing with the shooting well.

The man Mr Fuller is accused of threatening, conservative Tucson Tea Party co-founder Trent Humphries, said he was worried about the threat, and the dozens of other angry e-mails he has received.

"I had nothing to do with the murders that happened or the shooting of Gabrielle Giffords," said Mr Humphries, who was on his way to attend services for his friend Dorwan Stoddard, 76.

"And I wonder, if he (Fuller) is crazy or is he the canary in a coal mine? Is he saying what a lot of other people are holding in their hearts? If so, that's a problem."