A fire broke out at the Gallo Glass plant just after noon today, sending huge plumes of black smoke around the neighborhood just southeast of downtown Modesto.
There have been no reports of injury, and all employees at the plant have been evacuated, according to Susan Hensley, spokeswoman for Gallo.
It's the third reported fire at the plant in 17 months.
Hensley said today's fire occurred in one of the plant's furnaces.
As of 1:40 p.m., Hensley could not confirm if the fire was out or under control, or what damage occurred. Smoke could still be seen coming from the plant.
She said there are about 1,200 employees, but could not give a specific number as to how many were working on the shift when the fire was first reported.
The Modesto Fire Department, along with other emergency crews, arrived on the scene shortly after initial reports.
Two witnesses who arrived at the plant just after 1 p.m. said flames were not visible, although black smoke was still billowing out of the building.
This isn't the first time emergency crews have been called to the plant.
In June 2008, four employees were injured after a fire broke out in a furnace room.
In March 2008, fire crews were called to the plant after a similar fire in a different furnace. There are five on the compound.
In 2006, firefighters manned an 18-hour watch at the plant after another furnace spilled molten glass into a safety tank. No injuries were reported from than incident.