RCMP officers searched a condo in Saint-Hubert on Montreal’s South Shore on Monday in connection with a letter that was mailed to the White House and tested positive for the poison ricin.

Law enforcement cordoned off a lengthy stretch of a street lined by condo buildings in the suburban municipality. Local police and ambulance services were also at the scene.

Charles Poirier, spokesperson for the Quebec division of the RCMP, said a team of officers with expertise in handling chemicals and explosives is leading the search and neighbouring residences in the building have been evacuated.

“The RCMP is assisting the FBI in this investigation,” he said.

Poirier said there’s a link between a woman suspected of sending the ricin-laced envelope and the residence being searched.

WATCH | RCMP give update on search: 

RCMP in Quebec say they’re assisting the FBI in an investigation into suspicious packages that were mailed to the White House and other places in the United States. 3:08

The woman suspected of sending the envelope who was arrested over the weekend at the Peace Bridge border crossing between Fort Erie, Ont., and Buffalo, N.Y., has been identified as Pascale Ferrier, according to U.S. court records provided to CBC News.

Ferrier was supposed to appear in court Monday, but her appearance has been delayed until Tuesday afternoon, according to a spokesperson for the United States Attorney’s Office.

Police take part in an operation on Vauquelin Street in Saint-Hubert, Que., Monday. An RCMP spokesperson said there is a link between a woman suspected of mailing a ricin-laced letter to the White House and the residence being searched. (Ivanoh Demers/Radio-Canada)

The letter was intercepted at a U.S. government facility that screens mail addressed to the White House and President Donald Trump and a preliminary investigation indicated that it tested positive for ricin, law enforcement officials told The Associated Press.

Stéphanie Félix, who lives near where the raid was being carried out Monday, said she was “shocked” to find her quiet neighbourhood at the centre of an international police investigation.

“It makes you scared,” she said.