Fire officials say a deadly Northern California wildfire that is now raging into its fourth day and has destroyed more than 500 buildings, threatening thousands more, did not grow as dramatically overnight, though crews are still struggling to corral it.

As of 9 a.m. local time, crews were gaining control of a small wildfire in California’s wine-country county of Napa, but two blazes farther north are raging mostly unchecked.

The California Department of Forestry and Fire Protection said the blaze around Lake Berryessa in Napa County that destroyed seven structures was 50 percent contained as of this morning.

That fire broke out Saturday, forcing evacuations and burning 150 acres. Meanwhile, two fires in Mendocino County, about 100 miles northwest, have consumed 39 square miles and destroyed four homes.

Cal Fire spokeswoman Tricia Austin said this morning those blazes were each 5 percent contained. The fires, which have forced evacuations, currently threaten more than 4,500 structures.