The youngest victim of the mass shooting in Arizona was mourned in the state capital on Thursday, with her family escorting her small casket into a church as children her age wept.

Hundreds of mourners, many clad in white T-shirts, stood along a road close to the church in a show of support. About 20 people dressed as angels.

An American flag that was recovered from the site of the 9-11 attacks in New York City was raised outside the church as a tribute to Christina Taylor Green, who was born on the day the World Trade Center was destroyed.

Christina's funeral is the first for the six people who were killed Saturday morning at a public event held by Congresswoman Gabrielle Giffords in Tucson, Ariz.

The third-grade student had said to her parents that she hoped to attend Penn State University before setting out on a career to help less fortunate members of society.

Christina was also the only girl on her baseball team, and had aspired to become the first female player in Major League Baseball.

She had also recently been elected to her student council and had attended the event because of an interest in politics, something that President Barack Obama spoke of at a memorial service for the shooting victims on Wednesday night.

"She saw all this through the eyes of a child, undimmed by the cynicism or vitriol that we adults all too often just take for granted," Obama said.

"I want to live up to her expectations. I want our democracy to be as good as Christina imagined it. I want America to be as good as she imagined it."

Giffords' condition improves

While family, friends and strangers gathered to remember the young girl, new information came to light about the condition of Giffords, who was one of 13 people injured in the shooting.

The 40-year-old, three-term Democrat was gravely wounded, suffering a gunshot wound to the head from point blank range.

Neurosurgeon Dr. Michael Lemole said Giffords is now opening her eyes, moving her legs and arms and responding to friends and family.

Her doctors described that as a "major milestone" in her recovery.

"We're hoping that she crosses through many more," Lemole said.

Giffords first opened her eyes on her own Wednesday evening, while close friends from Congress and her husband, astronaut Mark Kelly, were visiting her in hospital.

"Gabby, open your eyes, open your eyes," Kelly said.

When he asked her to give him a thumbs up if she could hear him, Giffords raised her left arm.

Obama mentioned the incident in his speech at the memorial hours later, and the crowd broke out in applause.

More on the suspect

Jared Loughner was taken into custody after the shooting and was soon charged with five federal counts: the attempted assassination of a member of Congress; two counts of killing an employee of the federal government; and two counts of attempting to kill a federal employee.

On Thursday new details surfaced about his increasingly odd behaviour at school over the past year. The 22-year-old shocked one of his teachers in February with a comment about blowing up babies. From there things apparently went down hill for him.

According to 51-pages of police reports released on Wednesday, Loughner's behaviour became more unpredictable and unsettling in the months that followed. He was finally judged by Pima Community College to be mentally unbalanced and was suspended from attending class.

On Wednesday, police also revealed Randy Loughner, Jared's father, discovered his son had stolen a black bag from the family car hours before the shooting.

When he confronted his son about the issue, Jared Loughner fled from his father, police said.

Hours later, a shooting killed six people and left 14 others injured.

Loughner was living with his parents in Tucson at the time of his arrest. Those who know him have described Loughner as a loner who was becoming isolated and increasingly distant from mainstream beliefs and behaviour.

With files from The Associated Press