Police say the fired worker who killed five people at a manufacturing warehouse in Aurora, Ill., on Friday was able to buy the gun he used because an initial background check didn't catch that he had a prior felony conviction in Mississippi. Aurora Police Chief Kristin Ziman said Saturday that 45-year-old Gary Martin was issued a firearm owner's identification card in January 2014 after he passed the initial background check. She said he bought the Smith & Wesson .40-caliber handgun on March 11, 2014, and that his 1995 felony conviction for aggravated assault in Mississippi wasn't flagged until he applied...