By Dan Eggen
Washington Post Staff Writer
Wednesday, February 4, 2004; Page A07

The U.S. Secret Service intercepted a letter addressed to the White House in November that contained a vial of the toxin ricin, but never revealed the incident publicly and delayed telling the FBI and other agencies, law enforcement sources said yesterday.

The letter, signed by "Fallen Angel" and containing complaints about trucking regulations, was nearly identical to one discovered Oct. 15 at a Greenville, S.C., mail-sorting facility. It was accompanied by a metal vial that contained powdered ricin, sources said.

In the South Carolina case, the Centers for Disease Control and Prevention was called in to test the mail facility and its workers. The FBI also released detailed information about the case and, earlier this month, announced a $100,000 reward for information leading to a conviction.

But the existence of a similar letter sent to the White House was not disclosed until yesterday, and then only by law enforcement officials who asked not to be identified by name.

Six sources in law enforcement and public health said the Secret Service did not immediately inform the FBI, the U.S. Postal Inspection Service or other agencies about the White House letter when it was discovered. Three of those sources said the delay lasted "weeks," while a fourth recalled a lag of about nine days. Several said the delay was long enough that anyone exposed to the ricin would have begun to show symptoms.

"We did not get involved in any reasonable amount of time," one law enforcement official said. "The whole thing was kept under wraps on a national security basis."

Senate Majority Leader Bill Frist (R-Tenn.), whose office was the site of the latest ricin scare, and Minority Leader Thomas A. Daschle (D-S.D.), recipient of one of the anthrax mailings in 2001, declined to comment. But aides said they were unaware of the incident before yesterday.

Secret Service spokeswoman Ann Roman declined to comment on details of the case or why it was kept secret, citing the ongoing investigation. Roman also declined to say whether workers at the mail facility were tested or underwent decontamination procedures, and said the facility's location was kept secret for security reasons. Officials have previously said that one mail facility used by the White House is located at Bolling Air Force Base. The letter is believed to have been sent from the Chattanooga area as it passed through a mail facility there, a law enforcement source said.

A law enforcement official in the administration, who declined to be identified by name or agency, said the letter was discovered in November at "an offsite mail facility" used by the White House and that it contained "a fine powdery substance" that "tested positive for ricin."

"It was . . . determined that there was no public health risk because of the low potency and granular form of the substance," the official said.

CDC officials said that scientists in the unit that would handle such an investigation do not recall being told about the White House letter. "I don't know of any involvement by the CDC," a spokesman said. It is unclear whether any other agency might have conducted medical tests.

In October, postal workers at a Greenville, S.C., mail facility that serves a regional airport discovered an envelope marked: "caution RICIN POISON Enclosed in sealed container Do not open without proper protection."

Inside the envelope was a metal key chain vial containing white powdered ricin. The envelope also contained a typewritten letter identifying the writer as a fleet owner of a tanker company and protesting regulations mandating more rest hours for truck drivers on the road. No arrests have been made in the case.

The letter writer also claimed to have the ability to make large quantities of ricin and threatened to use the poison if the regulation changes were not dropped. The rules went into effect as scheduled Jan. 4. The envelope in Greenville was addressed to the U.S. Department of Transportation, according to a DOT spokesman.

The CDC conducted environmental assessment and sampling at the Greenville postal facility where the letter was discovered. The agency also interviewed all 36 workers at the facility and initiated a statewide surveillance for the appearance of disease or illness consistent with ricin exposure.

On Monday, authorities announced that a white powdery substance found near a pile of mail in Frist's office had been tentatively identified as ricin, and further tests yesterday confirmed the presence of the poison, which is made from castor beans.