Anthrax found in new location at Hart Senate office building

WASHINGTON (CNN) -- Anthrax was discovered in a new location of the Hart Senate Office building Wednesday night, at the same time officials were preparing to open three other congressional facilities on Capitol Hill, investigators said.

The building, which houses the office of Senate Majority Leader Tom Daschle -- where an anthrax-laden letter was delivered more than a week ago -- also showed a positive reading for anthrax in the southwest quadrant next to a freight elevator on the first floor. Mail to the building is typically brought up that elevator, but it's not known if Daschle's letter took that route or not.

The southwest corner of the building has been sealed off.

The southeast corner of the Hart building -- where Daschle's office is located -- had already been put off limits for decontamination. The other two quadrants of the building remain open.

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The clean-up process has begun in the mail rooms of the Dirkson Senate Office building and the Ford House Office building. An anti-bacterial foam will be applied, and then the rooms will be sealed for an undetermined amount of time.

Thursday, the Canon and Rayburn House Office buildings will reopen, as will the O'Neil storage annex. Friday the Ford House Office building reopens. The plan is for the Longworth House Office building to reopen Monday.

Senators or their staff members will be permitted back into the Dirksen and Hart Senate Office buildings -- with written authorization -- to retrieve items from their offices.

Since many senators said they left items for personal and professional business in their offices, Dr. John Eisold, the attending physician of the Capitol, said in a statement that "based upon all the results of nasal swabs and environmental testing to date, the Office of the Attending Physician has now determined that provision can be made for senators, or one staff member with the senator's written authorization, to re-enter the Dirksen and Hart Senate Office buildings."

Senators with offices in the southeast and southwest quadrants of the Hart Senate Office building, however, will not be allowed to enter. Both are off limits due to positive anthrax tests.

"Each senator will determine whether or not to re-enter their individual suite, or authorize their staff member to re-enter, based upon consultation with the Attending Physician," read Eisold's statement.

Daschle said he hopes the Dirksen Senate Office building will re-open Friday. Congressional sources said it could be "weeks" before senators and their staff will get back into the Hart building -- particularly the areas near Daschle's office.

The third Senate office building, Russell, re-opened for business Wednesday.

--CNN Capitol Hill Producer Dana Bash contributed to this report