Car fire spreads to vegetation along the Altamont Pass

Fire at Westbound I-580 and Flynn Road in North Livermore.

A car fire spread to vegetation in the Altamont Pass on Thursday night. Fire officials say the fire has spread to 100 acres. 

Alameda County Fire Department said the fire started at 9:45 p.m. and that the car owner called the emergency in to dispatch. 

Crews are responding to westbound I-580 and Flynn Road in North Livermore. 

Officials advised people to avoid the area and that the fire is spreading at a moderate rate of speed. 

It is not clear how the car fire started. 

No structures are threatened. Cal Fire is the lead agency fighting this fire. 

This is a developing news story.