Riverside County Fire Department crews responded to a report of a smoke coming from the Santa Rosa Apartment Homes complex in Wildomar, it was reported.
The incident occurred shortly before 9 p.m. Monday evening in the 36000 block of Yamas Dr. in Wildomar.
According to reports from the scene, firefighters made quick work of the mystery smoke, using chainsaws to access through the rooftop of the structure, while additional crews entered the building with water hoses.
Dozens of residents and onlookers lingered outside, watching as firefighters quickly secured the scene.
The extent of the damage to the structure and the source of the smoke was not known at press time.
It is not believed that there were any injuries at the scene.
This is a developing story.
Stay with SWRNN for details as the come available.
*Joe Fanaselle contributed to this report.