UPDATE: The U.S. Forest Service says the 517-acre Voltaire Fire in Carson City is nearing 100% contained. Officials said it should be fully contained by 6 p.m. on Thursday night. Voluntary evacuations have been lifted.

The fire started west of Carson City in Voltaire Canyon just after 8 p.m. on Tuesday.

Carson City Sheriff Ken Furlong tells us someone was burning human waste and subsequent flames spread to nearby brush. 

Sheriff Furlong says they've interviewed multiple people, and they are cooperating with the investigation. 

With our warmer weather, more people will want to go camping, but fire crews say we all need to be careful. 

"Carry and be prepared with water, a shovel and clear space. We also have plenty of campgrounds with designated fire rings which is also a good option," says Marnie Bonesteel, U.S. Forest Service, Humboldt Toiyabe National Forest.

Crews will be working for the rest of the night - while wind is minimal - to help contain the fire. 

The Forest Service says the fire is visible to area residents and people traveling on South Carson Street.  

Officials said there's a buffer between the fire and Casino Fandango because of burn scars from a wildfire last year.

One injury has been reported - a firefighter who hurt his knee.