A perimeter was set up around the site after police received a call at 5:30 a.m. A similar incident shut down the work site yesterday as well.
“The investigation is still going on concerning the other cases,” said Montreal police Const. Raphaël Bergeron.
"We’re going to look at a possible link between them, but the investigation into [the latest incident] is just starting”
In the previous incidents, approximately 1500 workers were sent home and delivery trucks were being turned away at the site gate.
Investigators are now on scene at the Glen Yards site searching for anything suspicious.
Construction workers across Quebec returned to job on July 2, after provincial legislation called an end to a two-week strike.
The latest incident comes on the last day of work before the province’s annual construction holiday.