FILE - In this Jan. 14, 2013 photo, New York City Mayor Michael Bloomberg speaks at a gun violence summit at Johns Hopkins Bloomberg School of Public Health in Baltimore, where he outli

 

              FILE - In this Jan. 14, 2013 photo, New York City Mayor Michael Bloomberg speaks at a gun violence summit at Johns Hopkins Bloomberg School of Public Health in Baltimore, where he outli
FILE - In this Jan. 14, 2013 photo, New York City Mayor Michael Bloomberg speaks at a gun violence summit at Johns Hopkins Bloomberg School of Public Health in Baltimore, where he outlined his proposals for federal gun control reforms. Police said Wednesday, May 29, 2013, that threatening letters containing traces of the poison ricin were opened Friday, May 24, 2013 at New York City’s mail sorting facility and Sunday, May 26, in Washington at the headquarters of the nonprofit started by Bloomberg, Mayors Against Illegal Guns. Both were addressed to Bloomberg and contained threats referencing the debate on gun laws. (AP Photo/Patrick Semansky, File)