U.S. Representative Gabrielle Giffords of Arizona and six others have died after a gunman opened fire at a public event on Saturday, Pima County sheriff's office in Arizona confirmed to National Public Radio.
A gunman ran up to Giffords, 40, and shot her in the head as she addressed supporters outside a Safeway grocery store, according to media reports.
The gunman was in custody, according to media reports.
Giffords, who was re-elected to her third term in November, was hosting her first "Congress on Your Corner" event at the store in northwest Tucson, NPR reported.
Giffords, 40, a Democrat, is married to U.S. astronaut Mark Kelly. She took office in January 2007, emphasizing issues such as immigration reform, embryonic stem-cell research, alternative energy sources and a higher minimum wage.
Earlier events in Tucson, Oro Valley, Green Valley, Sierra Vista, and Douglas had attracted between at least a crowd of 150, according to a statement announcing the event.