SAN FRANCISCO (AP) — Hundreds of lightning strikes overnight have sparked three dozen new wildfires in Northern California, authorities said Sunday.

The 36 blazes triggered by 800 lightning strikes were small and many were quickly put out, according to the California Department of Forestry and Fire Protection.

Many of the lightning-caused fires torched trees in rugged terrain that’s only accessible by hiking, the U.S. Forest Service said.

Meanwhile, about 3,000 firefighters continued to make progress on five large wildfires around the state.

Showers on Sunday helped crews make gains on a wildfire in the San Bernardino National Forest, which barely grew in size overnight.

The blaze, which erupted on June 17, was 50 percent contained after scorching 48 square miles of desert brush and forest timber. Firefighters hoped to take advantage of the weather to mop up and further surround the fire.

Authorities reopened a highway, and mandatory evacuations were lifted except for community of Burns Canyon. Hiking trails and camp sites remained closed. The firefighting effort has cost $27 million so far.

The fire destroyed a house and three out-buildings. A team of experts “will continue to evaluate the fire area for further damage,” the Forest Service said in a statement.

Four firefighters were treated for injuries. The cause is under investigation.

Firefighters reported making headway on other fires. A 118-acre fire outside the city of San Bernardino was 95 percent contained. A 500-acre blaze in Madera County sparked by a vehicle was 97 percent surrounded. A 19-acre fire in Napa County was 80 percent contained.

A fire caused by lightning in Alpine County south of Lake Tahoe was 37 percent surrounded after burning about 27 square miles since Friday. The fire continued to smolder, mostly in the wilderness.