US congresswoman Gabrielle Giffords of Arizona has been shot in the head at point-blank range outside a supermarket in the city of Tucson while holding a public event.

US news agencies reported that Giffords and six others had died, but a hospital statement on Saturday said that Giffords was undergoing surgery and did not confirm any fatalities.

Nine other people, including one child, had been admitted and were being treated for gunshot wounds.

US news broadcaster National Public Radio (NPR) reported that Giffords and three members of her staff were shot by an unidentified gunman who ran up and fired at the politician before apparently shooting indiscriminately.

Barack Obama, US president, issued a statement calling the incident an "unspeakable tragedy", saying that some victims had died while Giffords was "gravely wounded".

Al Jazeera's Nick Spicer, reporting from Washington DC, said that according to eyewitnesses, "bodies were lying on the sidewalk" outside the Safeway supermarket.

He said that "there were a lot of bullets flying" on the scene and that some people have been killed, but it's unknown how many or if Giffords was among them.

Giffords, he said, had been the target of threats and Giffords' office had been vandalised.

Republican criticism

Spicer said that Giffords was seen by Republicans as one to beat in the recent US midterm elections and was heavily criticised by 2008 vice-presidential candidate Sarah Palin.

"She was not somebody who was appreciated by the right wing of the Republican party," Spicer said.

"She had been singled out as someone who should be beaten at the polls, certainly, and she was somebody who supported healthcare reform which is really the landmark policy of Barack Obama's first term."

On the morning she was shot, Giffords was hosting a "Congress on the Corner" event - something she advertised on to her constituents as an opportunity to meet her and to discuss their concerns.

Chris Patyk, programme director of Tucson's KNST radio station, told Al Jazeera that Giffords is known for being "very personable" and that "it is easy to gain access and speak to Representative Giffords at an event like this, and that is why this news is all the more harrowing".

According to NPR, the suspected attacker, described as a male in his 20s, was "tackled by a bystander and taken into custody".

Giffords focused on immigration reform, military issues, stem cell research and alternative energy, as well as being a supporters of gun rights, while serving in Congress. She was married to US astronaut Mark Kelly.


Al Jazeera and agencies