The Secret Service confirmed that agents did indeed discover an envelope sent to the White House was laced with cyanide.
The news blog Intercept first alerted on the issue. The site reported an enveloped wrapped in a plastic bag and sent to the White House Screening Facility tested positive for cyanide.
“An envelope containing an unknown milky substance, in a container wrapped in a plastic bag, received at the White House Mail Screening Facility, tested positive for cyanide,” the Intercept reported, citing an internal law enforcement document that it obtained.
The return address on the envelope was for a man with a record of interaction with the Secret Service that goes back to 1995, when he was discovered to have sent a package to the White House covered in urine and feces.