An American flag flies at half-staff over the White House in Washington, Saturday, Sept. 19, 2020. (AP Photo/Patrick Semansky)
Three law enforcement officials say a woman suspected of sending an envelope containing the poison ricin, which was addressed to White House, has been arrested at the New York-Canada border.
The officials say the woman was taken into custody by U.S. Customs and Border Protection officers and is expected to face federal charges.
RCMP have said the letter addressed to the White House appeared to have originated in Canada.
Officials say it was intercepted at a government facility that screens mail addressed to the White House and President Donald Trump and a preliminary investigation indicated it tested positive for ricin.
The officials were not authorized to discuss the ongoing investigation publicly and spoke on condition of anonymity.
The RCMP says it's conducting an operation south of Montreal in connection with an envelope containing the poison ricin that was sent to the White House.