This article was last updated at 9:21 p.m. on September 11, 2021, by SCVNews staff.

Firefighters are expected to continue to battle the Route Fire through the night after it reached 400 acres on Saturday, shutting down both sides of the I-5 freeway into the evening, according to officials with Angeles National Forest. Three helicopters — two from the Los Angeles County Fire Department and one from the Angeles National Forest — are expected to continue making overnight water drops on the fire.

Caltrans officials announced shortly after 9 p.m. Saturday that two lanes going each direction on the I-5 were reopened.

Santa Clarita Valley Sheriff’s officials reported around 8:30 p.m. that “the structure threat appears to be mitigated at this time.”

Original Article from the Santa Clarita Valley Signal from Saturday, September 11, 2021 at 5:53 p.m.

Firefighters responded to the 50-acre Route Fire near Interstate 5 at Templin Highway in Castaic Saturday afternoon just before 4 p.m.

Matt Klein, acting supervisor with the Los Angeles County Fire Department, said containment was at 0% as of 5:15 p.m. Saturday.

The U.S. Forest Service is leading the effort to knock down the fire, while the county assists, he said. Officials have not called for evacuations, though Interstate 5 had been closed in both directions.

Traffic backs up on the northbound Interstate 5 where CHP officers have issued a SIG Alert for an unknown duration at Templin Highway. Bobby Block / The Signal.

The southbound Interstate 5 is closed at Vista Del Lago Road, while the northbound direction is closed at Templin Highway, according to an advisory issued by the Santa Clarita Valley Sheriff’s Station.

The California Highway Patrol issued SIG alerts for unknown durations at those locations, according to California Highway Patrol Officer Stephan Brandt.

He said he recommends avoiding traveling to the area as CHP officers are directing vehicles to exit the freeway and turnaround.

An ambulance drives past traffic on the northbound Interstate 5 toward where firefighters are battling a 50-acre fire near Templin Highway. Dan Watson / The Signal.

“It’s better off to avoid the area for a while until we have some kind of update on how long this is going to last,” he said.