A package addressed to President Donald Trump that tested positive for the poison ricin was intercepted by federal authorities in the past week, a law enforcement official said Saturday.
The official said the FBI, Secret Service and U.S. Postal Service inspectors are investigating the source of the package. Mail addressed to the White House is screened at an off-site location.
Ricin, a poison drawn from the husks of castor beans, has surfaced in other plots targeting Trump and other officials.
In 2018, a federal grand jury returned a seven-count indictment against a Utah man, alleging that he threatened Trump and other administration officials in letters, some of which contained the natural ingredients used to make ricin.