UPDATE, 2:47 p.m.: Broadcast traffic indicates the Cabin Fire burning well north of Azusa is at over 100 acres and growing.
Zak Bushey is en route to the fire.
PREVIOUS: A brush fire has ignited in the San Gabriel Mountains north of Azusa Friday afternoon.
The fire ignited around 1:10 p.m. near Highway 39 and Rincon Redbox Road. At least ten acres have burned so far and fire fighters report the flames have a rapid rate of spread.
Fire fighting aircraft are helping the nine engines and three hand crews, the US Forest Service reported on KTLA News.
Local media reports that possibly one structure has already been lost and aerial footage showed another structure already burning.
Glendora Police report that there is no threat to the city.
This story will continue to be updated as information becomes available.