Firefighters made progress toward containing northern California’s Lucas fire, state officials said on Sunday.

Fire officials are still investigating the cause of the fire, which has burned more than 4,120 acres across Lake and Mendocino counties. The fire was 30% contained by Monday morning, according to the California department of forestry and fire protection, or Cal Fire.

“We do feel like today was a big turning point for us,” Ryan Isham, Cal Fire’s operations section chief, told a crowd of 100 community members in the northern California town of Upper Lake on Sunday.

“We are still going to be on the fire for several days to come, continuing to reduce the risk,” he added.

Nearly 900 people fled the area after officials imposed evacuation orders. No one has died or gone missing, though a man was arrested for trying to jump a roadblock, said Lake county’s sheriff, Luke Bingham.

The fire started on Thursday. It will continue to produce significant smoke in the area as firefighters work to hold it back on Elk Mountain, which caught flame more recently, Isham said.

Cal Fire, working jointly with the Lake county sheriff’s office, had deployed 163 engines, along with 72 crews, dozens of water tenders and eight helicopters to halt the blaze.

Mendocino national forest ordered an emergency closure of parts of its grounds and campsites last week due to the fire.