WINDSOR, ON—Police have confirmed that they believe the explosion at Stellantis’s assembly plant here on Nov. 4 was “a deliberate act.”

Police went to the plant around 5:45 p.m. and found suspicious items at the scene of the explosion. The explosion took place on the west side of the plant on the second floor in an area that is used for storage.

The plant resumed production the following morning, Nov. 5, and the Windsor Police also spent the morning at the factory.

“Investigators do believe this was an intentional act and are seeking any information that may help identify a suspect or suspects,” wrote Windsor Police Services Corporate Communication Constable Talya Natyshak.

Workers were sent home late Thursday afternoon before police arrived at 5:45 p.m. as a precaution. The explosion didn’t cause any injuries.

In a posting on Unifor Local 444’s Facebook page, president Dave Cassidy confirmed the union was co-operating with the police investigation and delivered a stern message to his membership.

“It is essential to make sure when our members go to work, they feel safe and secure,” Cassidy wrote. “Over the last couple of weeks, there have been some incidents going on in the plant based on anxieties. I know we have had some hard news as of late, but any lashing out in the facilities cannot and will not be accepted and needs to stop.”

The source of the tension in the plant is Stellantis’s recent decision to eliminate the second shift in April due to the global microchip shortage that’s limited production and the lingering effects of the COVID-19 pandemic.

Another irritant for workers is the company’s mandate that all its employees must be vaccinated by mid-December or risk discipline. They could even be fired.