Emergency services personnel responded to Imperial's Sarnia manufacturing site Tuesday evening after a tower collapsed.
The structure collapsed inside the plant near the roadway, triggering plant emergency sirens.
Imperial issued a statement shortly after the incident which said all workers had been accounted for.
"The tower was out of service at the time [of the collapse] and being prepared for plant maintenance," Imperial said. "We have activated our incident command centre and are working with local authorities. As a precaution, our emergency responders are spraying water on the structure. Community members will notice high flaring from the site. This measure is part of our emergency response processes. We have initiated air monitoring as a precaution."
Imperial said while the sirens sounded at the plant, no action is required on the part of the community.
A Chemical Valley Emergency Coordinating Organization (CVECO) Code 6 has also been issued by Imperial and full traffic control has been requested in designated areas.
Sarnia police have closed Vidal Street South between Confederation Street and Churchill Road. Barriers have been set up at Vidal Street South and Clifford Street to the north and Vidal Street South and Kenny Street to the south. Tashmoo Ave at Kenny Street has also been closed.
BlackburnNews.com will provide more information as it becomes available.