Arizona shooting: Survivors relive supermarket horror
Survivors of the Tucson shootings have told of the terrifying moment a gunman shot Congresswoman Gabrielle Giffords and then began firing indiscriminately into a crowd of people before being wrestled to the ground.
One minute Ms Giffords "was talking to a couple and smiling", said Doctor Steven Rayle. Seconds later, the doctor said, "I saw a man shoot her in the head and then he began just spraying gunfire everywhere."
"He was ready for war, he was not playing around," Joe Zamudio told CNN television. "He was blank. He was callous, almost."
Witnesses said gunman Jared Loughner, 22, fired between 15 and 20 rounds in quick succession in an area of the Safeway supermarket where some two dozen people were closely gathered.
The fact that six people - including a nine-year-old girl, one of Ms Giffords' staffers, a federal judge and three retirees - were killed, and more than dozen people were injured suggests how easily the gunman was able to target victims in the enclosed space.
"He just continued firing," said Dr Rayle. "I was a bit stunned for a brief moment and then I got behind a concrete stump that was there. As he continued firing, I got down on the ground. I acted like I had been shot and was dead so I wouldn't be a target."
Amid the chaos some were thinking clearly enough to take decisive action.
As the gunman paused to reload, witnesses described how a middle-aged lady wrestled the gunman's next ammunition magazine from his hand.
Police said that he managed to put another magazine into his firearm, but its spring failed and at this point two male bystanders launched themselves at the killer. Their desperate bid to halt the carnage was successful.
Mr Zamudio had been inside a nearby Walgreens when he heard the shots ring out.
"I ran outside towards the shots and when I rounded the corner, the first thing I saw was the people wrestling with the gunman," he said. "Behind that it was just kind of like people laying everywhere and kind of falling and crawling."
As people held down the struggling but silent gunman, Daniel Hernandez, an intern who was working for Ms Giffords, said he tried to administer first aid to the congresswoman until an ambulance arrived.
"I had to lift up the congresswoman because she was severely injured and I wanted to make sure she was able to breathe OK because there was so much blood.
"I don't know how much time it took, it seemed like it took an eternity but that's just because the way the events were unfolding because I was trying to make sure that I was holding the congresswoman so that she could still breathe well but also make sure I was holding her wounds so she didn't...so that she was in a good enough condition to be transferred to a hospital by an ambulance."