A test on an envelope that arrived at the White House Mail Screening Facility Monday indicates that it contains cyanide, according to the Secret Service. The agency did not announce to whom the letter was addressed; further tests are being conducted to confirm the results.
Secret Service Spokesperson Robert Hoback says:
"On Monday 3/16/15, an envelope was received at the White House Mail Screening Facility. Initial Biological testing was negative; however, on 03/17/15, the chemical testing returned a presumptive positive for Cyanide. The sample was transported to another facility to confirm the results.
"As this is an ongoing investigation, the Secret Service will have no additional comment."
The letter was first reported by news site The Intercept, which adds that the return address matches that of a man the Secret Service believes is responsible for other alarming packages received in the past 20 years.
News of the intercepted letter came on the same day that Secret Service Director Joseph Clancy was taken to task on Capitol Hill, in a budget hearing that focused on a string of recent misconduct by federal agents.