The package was spotted at a security checkpoint in the U.S. departures area at Trudeau early Sunday morning and police were called in, said Jean-Pierre Brabant, a Montreal police spokesman.
‘‘The suspicious package was controlled by the SWAT team, from there it was sent to a lab where there was some other evaluations made,‘‘ Brabant said.
Several local media outlets reported the U.S. screening area of the airport was closed and a number of American bound flights were delayed, though an airport spokeswoman said flight operations resumed later Sunday.
Police converged on the Montreal borough of LaSalle Sunday evening as a result of their investigation and blocked off a section of the neighbourhood.
At least a dozen emergency vehicles were on the scene and police said they were going to search an apartment in the neighbourhood.
"There is going to be an approach that is going to be made in an apartment to get all the information so we can find some items inside the house that‘s going to help us and lead us to what was really inside the suspicious package," Brabant said.
A 71-year-old suspect who had a plane ticket to fly out of Montreal was being detained but had not been questioned, said Ian Lafreniere, another police spokesman.
The items in the package were not explosives, but were "not the kind of items you take on a plane," Lafreniere said.
"I don't know anyone who would travel with these kind of objects," he said.
Lafreniere said everyone on the flight was questioned and luggage was searched as a precaution.
Roughly 20 residents were ordered from their homes from their homes. They were huddled around the edge of the perimeter, curious to find out what had happened.