Police had to be called to a rowdy United Auto Workers meeting on Sunday, after tempers flared between union leaders and the rank and file.
The plant is set to close on March 31, 2010, following decisions by Toyota and General Motors to end production in Fremont.
More than 4,700 workers are expected to lose their jobs.
And hecklers at Sunday's meeting claim their union bosses have not done enough to stop the shut down.
