Update 3:01 p.m.: Fire department units will remain on (the) Pico Fire scene throughout the night, increasing containment lines and extinguishing hot spots, according to an LACoFD tweet.

Update 2:49 p.m.:
Forward progress of the Pico Fire in Stevenson Ranch has been stopped at 90 acres, with 35 percent containment as of 2:49 p.m., according to county fire officials.

Original post 2:25 p.m.:
Los Angeles County and City firefighters are battling a fast-growing three-alarm brush fire that broke out in the Pico Canyon area of Stevenson Ranch in the Santa Clarita Valley early Monday afternoon.

Dubbed the Pico Fire, the three-alarm blaze had consumed 10 acres by 1:45 p.m. with zero containment. By 2:15 p.m., it had grown to 50-plus acres with no containment, according to the LACoFD.

“We received a call at 12:54 p.m., units were dispatched at 12:57 and they were on scene at 1:08,” a county fire assistant said. “It’s in the 26000 block of Pico Canyon Road,” just west of Pico Canyon Park in the 91381 Zipcode.

The fire had initially scorched four to five acres of medium brush, but by 1:45 p.m. it had spread to 10 acres with zero containment.

More than 220 firefighters are battling the blaze. The L.A. city fire department is also assisting, the county fire assistant said.

County fire officials have also requested assistance from water-dropping fixed-wing aircraft.

No structures are threatened and the fire’s cause is unknown, he said.

No evacuations have been ordered, but deputies from the Santa Clarita Valley Sheriff’s Station are monitoring the situation, according to the station’s Twitter feed, which added: “There are people driving up here that don’t live in the area just to check out the fire. Please avoid the area if you don’t need to be here, allow first responders to easily access streets.”

The Remote Automated Weather Station near the Pico Fire reported the temperature at 106°F with windspeed 7 mph, gusting to 15 mph out of the west and relative humidity of 19 percent.