FBI agents focus on New Jersey postal route

TRENTON, New Jersey (CNN) -- FBI agents Saturday canvassed residents along a postal route from where two letters containing anthrax are thought to have been sent.

One letter was sent September 18 to NBC anchor Tom Brokaw; the other was postmarked October 9 and sent to Senate Majority Leader Tom Daschle in Washington. Both letters were addressed in similar block-style handwriting.

Residents along the route said they were asked whether they recall having received anything suspicious.

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One of the residents, Jim Frascella, told CNN that FBI agents asked him whether he had seen any cars bearing Florida license plates in the area.

The mail route being investigated consists of about 250 homes and businesses in West Trenton.

The female letter carrier responsible for the route contracted cutaneous (skin) anthrax, possibly from handling anthrax-laced letters. The mail carrier picked up stamped letters and delivered mail only at the individual mail boxes on her route; she did not empty any collection boxes.

A second postal employee, a male mail sorter in the Hamilton Township facility, has also tested positive for skin anthrax. There is still a third possible case of skin anthrax involving a New Jersey postal worker, but tests so far have been inconclusive.

The West Trenton post office and the area's main mail processing and distribution center in Hamilton Township were closed Friday as investigators scoured the two buildings for clues to the origin of the strain of anthrax found in letters postmarked in Trenton and mailed to the Senate office building and NBC News.

FBI Special Agent Linda Vizi said agents have seized evidence in the Trenton area, but she would not specify what.

Investigators have focused on some cities in New Jersey since the September 11 terrorist attacks on the World Trade Center and the Pentagon.

Several of the hijackers are thought to have lived in an apartment in Paterson, New Jersey.

CNN Producer Dana Garrett contributed to this story.