WASHINGTON (AP) - The Secret Service says a letter similar to ones sent to New York Mayor Michael Bloomberg has been intercepted by a White House mail screening facility.
The agency says the letter has been turned over to the FBI's Joint Terrorism Task Force for testing and investigation.
Officials have said that two threatening letters postmarked in Louisiana and containing traces of the deadly poison ricin were sent to Bloomberg in New York and to his gun-control group in Washington.
Police said Wednesday one anonymous letters was opened Friday in New York at the city's mail facility. The other was opened Sunday in Washington at an office used by the nonprofit started by Bloomberg, Mayors Against Illegal Guns. Both were addressed to Bloomberg and contained threats referencing the debate on gun laws.
Police say the people who initially came into contact with the letters showed no symptoms of exposure to the poison, but three officers who later examined the New York letter experienced minor symptoms that have since abated.