A package containing the poison ricin and addressed to President Donald Trump was intercepted by law enforcement earlier this week, according to two law enforcement officials.
Two tests were done to confirm the presence of ricin.
All mail for the White House is sorted and screened at an offsite facility before reaching the White House.
A US law enforcement official said that investigators are looking into the possibility the ricin package sent to Trump came from Canada.
The FBI and Secret Service are investigating the matter.
Ricin is a highly toxic compound extracted from castor beans that has been used in terror plots. It can be used in powder, pellet, mist or acid form.
If ingested, it causes nausea, vomiting and internal bleeding of the stomach and intestines, followed by failure of the liver, spleen and kidneys, and death by collapse of the circulatory system.
“The FBI and our US Secret Service and US Postal Inspection Service partners are investigating a suspicious letter received at a US government mail facility. At this time, there is no known threat to public safety,” the FBI’s Washington field office said in a statement.
