DETROIT – The Jefferson North Assembly Plant was evacuated Saturday morning after a gunman entered the building and was subdued by union stewards.

An unidentified person with a gun entered the FCA plant on Conner Street.

The man was not a current employee, according to officials at FCA, but had previously worked at the plant eight months ago, according to Detroit Police Chief James Craig.

According to police, the gunman was having problems with a domestic partner that works at the plant. The suspect never brandished the weapon, but employees saw it and were able to contain him until police arrived.

Police took the man into custody. Craig called the union stewards who contained the gunman heroes.

“The courageous behavior of those union stewards, those fellow employees, who went into action and didn’t wait for the police, they saw that this could have been a tragic situation and went about the business of subduing the suspect and they did it quickly without an incident,” Craig said.

The plant has resumed operation.

There were no injuries and no shots were fired.

Craig said the man was wanted for a parole violation and that he is the person of interest in four or five carjackings that occurred Saturday morning across Detroit.

In September of 2012, a line worker stabbed and killed his union steward at the plant over a possible affair with his wife who also worked there. The line worker then drove to nearby Belle Isle and shot himself.

Stay with Local 4 and ClickonDetroit.com for updates to this developing story.