Six people died and 14 were wounded in the burst of violence a week ago outside a Tucson supermarket [AFP]

The US congresswoman who was shot in the head has been removed from a ventilator and is breathing on her own through a tube inserted into her windpipe, the University Medical Center in Tucson, Arizona, has announced.

Democratic congresswoman Gabrielle Giffords, who survived despite being shot through the head from point-blank range a week ago, remains in critical condition.

"A surgical procedure (tracheotomy) was performed this morning on the congresswoman to replace the breathing tube that ran down her throat with a tracheotomy tube in her windpipe, protecting her airway and freeing her from the ventilator," the hospital said in a statement posted on its website on Saturday.

"Her recovery continues as planned," it said. Surgeons also inserted a feeding tube.

Giffords, 40, opened her eyes for the first time minutes after Barack Obama, the US president, visited her Wednesday.

Six people died, including a federal judge and a nine-year-old girl, and 14 were wounded in the burst of violence a week ago outside a Tucson supermarket, where Giffords was holding a public event with her constituents.

The alleged attacker, Jared Loughner, a 22-year-old local resident, is in custody.

Christina Taylor Green, the youngest victim of the Tucson shootings, was laid to rest on Thursday, a day after Obama, hailed the 9-year-old as an inspiration to US politicians to heal their poisonous divisions.

Source: Agencies