Police in New York say preliminary tests of two threatening letters sent to Mayor Michael Bloomberg contained traces of ricin.
The anonymous letters, both addressed to Bloomberg, were opened Friday in New York at the city's mail facility and Sunday in Washington, D.C., at the headquarters of the nonprofit started by Bloomberg, Mayors Against Illegal Guns, according to authorities.
Reuters, quoting a police statement, reports that both letters "contained threats against Bloomberg and mentioned the gun debate."
Police say preliminary testing indicated the presence of the deadly poison ricin. They say mail sorting personnel who came into contact with the letters were not showing any symptoms, but that some officers who later examined the one in New York were, according to The Associated Press.
NPR's Dina Temple-Raston reports that the letters were going for secondary testing to confirm the results, because preliminary tests are sometimes inaccurate.
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