The person who sent two menacing letters tainted with the poison ricin to Mayor Michael Bloomberg and his gun-control advocacy group may also have sent a similarly worded letter to President Barack Obama, federal officials and a law enforcement source said, and late Thursday a Texas man was being questioned in the case.
The source said the man was neither arrested nor charged.
All three letters were postmarked May 20 in Shreveport, La., and had similar wording, federal officials said. The FBI had been operating under the theory all three letters were sent by the same person, one federal law enforcement source told Newsday.
In Spokane, Wash., federal authorities are investigating whether a man indicted there on charges he sent ricin-laced letters to Obama, a federal judge, the CIA, an Air Force base and a post office is connected with the Shreveport letters, the law enforcement source said.
In the Spokane case, Matthew Ryan Buquet, 38, was charged May 22 with a one-count grand jury indictment for mailing threatening communications, the FBI said. The letters he's suspected of mailing were addressed in handwritten red ink, according to the FBI.
The source characterized the man questioned in Texas as a "person of interest" who served in the U.S. military. He now is a civilian worker for the Department of Defense and has family and friends in Shreveport. He had not been identified as a suspect by late Thursday.
The source said one section of all three letters reads: "You will have to kill me and my family before you get my guns. Anyone who wants to come to my house will get shot in the face. The right to bear arms is my constitutional God given right and I will exercise that right till the day I die." Another part reads: "What's in this letter is nothing compared to what I've got planned for you," the source said.
Authorities have analyzed the two Bloomberg letters for fingerprints but have not found usable prints, the federal source said. All three letters are being or will be analyzed for DNA, he said. Testing of the third letter, to Obama, has not yet confirmed it was laced with ricin.
The "U.S. Secret Service can confirm that the White House mail-screening facility intercepted a letter addressed to the White House that was similar to letters previously addressed to Mayor Bloomberg in New York," the agency said in a statement. "This letter has been turned over to the FBI Joint Terrorism Task Force for testing and investigation."
Ricin is a chemical poison from the castor bean that prevents human cells from making the proteins they need to function. It can be used as a powder, a mist or a pellet, or can be dissolved in water or weak acid, according to the U.S. Centers for Disease Control and Prevention.
Bloomberg's office said Thursday the substance "did not appear to be in a form that could be inhaled or otherwise readily ingested. Touching the envelope or letter should not be a risk."
Kelly said Thursday that police are investigating two other incidents: a letter containing powder placed at the door of a city agency supervisor, and two letters sent to the Manhattan office of Public Advocate Bill de Blasio, a Democrat running for mayor.
The letters to de Blasio's office in the Municipal Building at 1 Centre St. were believed to be bloodstained, written in Spanish and probably sent by the same person, Kelly said.
The letter with powder was left at the door of a supervisor at the city's Department of Environmental Protection offices at 290 Broadway, near City Hall, he said.
One letter to Bloomberg was opened last Friday at a mail facility at 100 Gold St. near City Hall. "This envelope went [through] various screening processes and was isolated in a biochemical containment box and then removed by the New York City Police Department and Department of Environment Protection," the Bloomberg statement said.
Bloomberg visited workers at the mail facility Thursday "to thank them for their service," the mayor's office said. Kelly said three members of the police Emergency Service Unit were treated for diarrhea and other symptoms of exposure to ricin. The other Bloomberg letter was opened Sunday at the Washington, D.C., offices of the group he co-founded with Boston Mayor Thomas M. Menino.
A Mississippi man was arrested in April and charged with sending ricin-laced letters to Obama and two other officials.
With Robert E. Kessler, William Murphy and Maria Alvarez