FBI agents and Tucson area law enforcement officers scour the parking lot of the Safeway in Tucson, Ariz., on Monday, looking for evidence of Saturday's shootings. Two days after a mass shooting at the Safeway, the grocery store is closed and the parking lot a scene of intense law enforcement activity. (Associated Press)

FBI agents and Tucson area law enforcement officers scour the parking lot of the Safeway in Tucson, Ariz., on Monday, looking for evidence of Saturday's shootings. Two days after a mass shooting at the Safeway, the grocery store is closed and the parking lot a scene of intense law enforcement activity. (Associated Press)