US officials say they have found key similarities in two letters that contained the potentially deadly bacteria anthrax as fears over biological warfare mount across the US.
FBI Director Mr Robert Mueller said that since October 1st, his agency had received 2,300 reports involving anthrax or other dangerous agents, although the overwhelming majority turned out to be "false alarms or practical jokes." The Justice Department announced that federal prosecutors in Connecticut had brought charges against two men relating to hoaxes.
"Hoaxes, pranks and threats involving chemical or biological agents are serious crimes and warrant a serious response," Mr Mueller said during a Washington news conference with Attorney General Mr John Ashcroft.
Late yesterday, the US army confirmed that a letter sent to the highest-ranking US senator, South Dakota Democrat Mr Tom Daschle, contained anthrax bacteria spores.
Searches of media offices in New York, however, failed to detect fresh traces of anthrax but investigators believe they have established a link between the letter sent to Sen Daschle and one sent to NBC newsreader Mr Tom Brokaw.
Mr Mueller said there were similarities in the handwriting in anthrax-containing letters sent to anchorman Tom Brokaw of NBC News in New York and to Sen Daschle in Washington. The Justice Department released a copy of the front of each envelope. Both were postmarked from Trenton, New Jersey, and both hand written in similarly printed letters and numerals.
Two people linked to New York news offices, the 7-month-old son of an ABC News employee and an NBC News employee who handled a tainted letter, have contracted skin anthrax.
Mr Ashcroft said authorities believe there may be other similar envelopes in circulation. He said investigators had not yet linked letters tainted with anthrax to those responsible for the September 11th attacks on the US.
"Any time someone sends anthrax through the mail, it's an act of terror. It's terrorism, and we treat it as an act of terror and terrorism," Mr Ashcroft said. "While we have not ruled out linkage to the terrorist attack of September 11 or the perpetrators of that attack, we do not have conclusive evidence that would provide a basis for our conclusion that it is a part of that terrorist endeavor."