The fire was 50 percent contained as of 8 p.m., according to fire officials, who said structures were no longer threatened and no evacuations were required.
Earlier in the evening, officials said the fire posed a small threat to the city of Duarte and the MTA Gold Line track.
Winds up to 10 mph pushed the fire toward the nearby MillerCoors brewery, where a structure defense was established, officials said.
At least five water-dropping helicopters were assisting firefighters on the ground.
Brush fire scorches 30 acres, threatens structures in Irwindale
There has been one civilian injury reported due to smoke inhalation.
The fire was first reported at around 5:40 p.m.