N.J. post office begins more anthrax testing

Results from previous testing expected Wednesday

NEW YORK (CNN) -- While post office and health officials in New Jersey awaited results from anthrax testing in two postal facilities, experts were testing Wednesday in three others.

The five sites together make up the network that transfers or processes mail from Princeton, New Jersey. A Princeton mail collection box was removed Friday after traces of anthrax were found in it.

Officials do not believe the spores found are new, said U.S. Postal Service spokeswoman Diane Todd. Rather, she said, the assumption is they are residual and may have been missed during testing last fall.

Results from anthrax tests on 37 environmental samples from the Monmouth and Kilmer postal facilities, delivered to the New Jersey Department of Health on Monday morning, now are not expected back until Thursday morning.

Todd says the decision to begin new testing at the Princeton Post Office and dock transfer locations in Hamilton and South River is "totally precautionary." Those sites would have been tested had results from earlier tests come back positive. But given the mail flow through the system and the time it takes to test the samples, officials decided to move ahead as a precaution.

Five people died last fall after anthrax-laced letters were sent through the mail to members of Congress in Washington and to television network offices in New York. Several other people were infected, but recovered.