UPDATE: The fire is 100% contained, the Boulder County Sheriff's Office said in a tweet just before 5:30 p.m. You can read our original story below.
DENVER — Crews from Boulder Fire-Rescue and the local sheriff's office are responding to a grass fire burning north of Boulder that is being called the Lakeridge Trail Fire, which is 75% contained as of 4:30 p.m.
The fire was first reported at 2:20 p.m. around N. Lakeridge Trail and Allens Lake.
As of 2:55 p.m., the fire was estimated to be 8-10 acres in size, according to the Boulder County Sheriff's Office. Four homes were evacuated in the area but no structures were on fire.
Highway 36 was shut down at 3 p.m. between Neva and Nelson roads because of smoke causing traffic backups, the sheriff's office said. But just after 4 p.m., the sheriff's office said Highway 36 would be opening back up. Closures for Mountain Ridge Drive and Lakeridge Trail will stay in place.
Around 3:15 p.m., the Boulder County Sheriff’s Office issued an evacuation warning for areas including Lakeridge Trail and Nelson Road because of the fire warning people to be ready to evacuate.
“If you need assistance or might need extra time, begin your evacuation now,” the sheriff’s office said.
Air resources are at the scene of the fire. As of 3:15 p.m., at least one slurry line had been dropped.
Heil Valley Ranch is closed as a precaution because of the fire.
Around 3:38 p.m., the sheriff's office said firefighters were starting to get containment on the fire, which was still estimated at around 10 acres.
At 4:30 p.m., the Boulder County Sheriff's Office said the fire was 75% contained.
This is a developing story and will be updated.