WASHINGTON, D.C (NBC)-- A letter addressed to President Donald Trump containing the deadly poison, Ricin, was intercepted earlier this week.
Authorities say the letter that tested positive for Ricin was detected at an off-site facility that screens mail addressed to the White House.
The FBI, secret service and U.S. Postal Inspection Service are investigating to determine where the letter came from.
The letter was detected at the screening facility, so it never reached the White House.