UPDATE (July 30, 2017 12:10p): Arson investigators are on scene and trying to determine what caused the fire. 

Officials said a train was threatened with fire, but was able to move out of the way. 

Crews are still on scene mopping up and putting out hot spots. 

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Fire crews are battling a grass fire near Highway 99 near Golden State Avenue. 

Initial reports are that fire is burning on west and east sides of highway 99. 

The fire started around 11:00 a.m. 

This is a breaking news story, check back for updates.