PHOENIX - President Barack Obama said Saturday that U.S. Rep. Gabrielle Giffords was gravely wounded after being shot at an event in Tucson Saturday morning. Arizona law enforcement officials say a gunman in the crowd shot Giffords, and a person in the crowd shot at the gunman. Five others have reportedly been killed after the shooting at a Safeway in northwest Tucson. Arizona state Sen. Linda Lopez, who is at University Medical Center in Tucson, said she spoke to Giffords' parents and they said she is in the emergency room undergoing surgery and is in very serious condition. But conflicting reports abound: CNN, FOX and NPR news, as well as KOVA-TV in Tucson, report that the congresswoman is dead; but MSNBC interviewed Pima County Sheriff Clarence Dupnik and he said that as of 2:25 p.m. EST, Giffords was still alive. More on the shooting from the Arizona Republic At least four people are dead, University Medical Center spokesman Darci Slaten said. They were among five to seven people who were being treated. The NBC affiliate in Tucson reported that the FBI has taken over the investigation. a man who works at a Sprint store nearby told CNN he heard 15 to 20 shots, and there were two bodies on the ground in front of the Safeway. He said people were screaming that ?Gabrielle Giffords has been shot.? Giffords was reportedly holding one of her Congress on Your Corner meetings with constituents when a gunman opened fire outside the store. Giffords, who got her Masters in Regional planning from Cornell in 1996, held the meetings regularly to listen to concerns from constituents. during a similar event in 2009 in Douglas, there was a tense moment when a protester who had brought a gun dropped the firearm and police were alerted. The 2009 meeting took place during the height of the fury over the health care reform debate. in an interview, Giffords was nonchalant about the incident. ?When you represent a district that includes the homes of the OK Corral and Tombstone, 'The Town too Tough to Die,' nothing's a surprise out in Cochise County,? Giffords said during an August 2009 meeting with The Arizona Republic Editorial Board. in November, Giffords a moderate Democrat, won re-election to her third 2-year term, narrowly defeating Republican businessman Jesse Kelly in a contentious race that centered largely on the issue of illegal immigration and border security, two hot-button issues in Arizona. Although immigration and border security played a role in every major race in the state, the debate was especially fierce in the 8th Congressional District. The District includes a 114-mile stretch of the U.S. border with Mexico. during the campaign, Giffords touted her efforts to push the Obama administration to deploy National Guard troops to the border and for playing an instrumental role in securing $600 million in funding to add more technology and Border Patrol agents. Kelly criticized Giffords for not doing enough and had called for the construction of a double-layer border fence, more Border Patrol agents and the deployment of 10,000 National Guard troops to the border, more than eight times the 1,200 sent by the Obama administration. At one point during the heated campaign, Kelly said Giffords had ?betrayed southern Arizona by refusing to secure the border.? Giffords opposed SB 1070, the state's new controversial immigration law, calling it ?divisive.? she supported instead comprehensive immigration reform at the federal level. The law sought to make it a state crime to be in the country illegally and to require police to question suspected illegal immigrants. Kelly supported the law, and opposed sweeping reforms in favor of stricter enforcement of existing laws. The American Civic Association in Binghamton was the site of a mass shooting the morning of April 3, 2009, when naturalized immigrant Jiverly Wong killed 13 people and himself, and wounded four others.