The justices of the U.S. Supreme Court had to get out of their building on Monday after anthrax was found in the mailroom. They're hearing cases a few blocks away in the federal courthouse.

It's the first time the justices have had to leave their home building since it opened in 1935.

A spokeswoman says the Supreme Court building won't open until at least Wednesday. "Based upon the positive testing in the mailroom, additional testing is being conducted today," said Kathy Arberg.

So far, anthrax has been detected in only one part of the mailroom in the basement. On Friday, anthrax was discovered at an external mail-sorting plant that handled mail for the court.

Officials from the Centers for Disease Control and Prevention announced two more confirmed cases of anthrax on Monday.

A New Jersey postal worker has the more dangerous inhaled form of anthrax. A New Jersey woman who doesn't work for the post office or the media has the skin form of anthrax.

The Bush administration said they're still learning about how to decontaminate buildings.

"We've got the best scientists the best doctors and bioterrorism experts in the country helping us in this endeavour," said Health and Human Services Secretary Tommy Thompson.

In New Jersey on the weekend, a female postal worker was diagnosed with inhalation anthrax, becoming the country's 15th case so far.

Officials from the CDC said the case, previously listed as suspect, was confirmed on Sunday.

Since September 11th's terrorist attacks, three people have died from the inhaled form of the disease and four are being treated in hospital.

And on Capitol Hill, the Hart Senate Office Building was to remain closed Monday. That's the building where Senate Majority Leader Tom Daschle received his anthrax-tainted letter three weeks ago.