Residents Told to Flee From Sierra Fire : Forests: Most opt to stay. Blaze started by spark from machinery. More than 4,800 acres around California/Nevada border are consumed.

Towering pines weakened by years of drought erupted in a firestorm that raged through more than 4,800 acres and burned at least three homes near this settlement west of Reno, officials said Friday.

No one was injured, and despite heavy smoke visible for dozens of miles, Interstate 80 remained open and busy with travelers crossing the Sierra.

“We’ve never seen anything like it. You could see the place exploding,” said Verdi volunteer firefighter Pete Hegge. “It just came down the canyon, then all hell broke loose.”

The Crystal Peak fire was reported just before 2 p.m. Thursday and raced through about 1,000 acres on the California side of the state line before it was three hours old. It began in Tahoe National Forest and spread into Toiyabe National Forest, sweeping downhill into Nevada.

Residents were advised to evacuate as the fire hovered near several subdivisions Friday, but most opted to stay.

“We’re watching the flames from our back-yard patio,” said Cindy Ballman, who vowed to “stay put as long as we can.”

Officials let only residents enter Verdi, a community of 1,200 just east of the California line, and chased away gawkers who lined the road into town to view the flames.

At the height of the fire Thursday, flames shot 100 feet into the sky and ash fell in Reno, 12 miles to the east. By Friday, calmer winds and higher humidity had set in, helping the 1,000 firefighters on the scene. At dusk, the fire was 25% contained.

Authorities said the blaze was apparently sparked by a piece of machinery operating in an area left tinder dry after eight years of drought.