Last week in either Napa or Sonoma County, some private citizens not assigned to the firefight apparently took it upon themselves to start lighting backfires to prevent the spread of the Glass Fire — an activity the Cal Fire takes seriously for its potential danger.

"You don't just arbitrarily put fire on the ground without notification," says Cal Fire spokesperson Scott McLean, speaking the Press Democrat. "There's so much danger to that. There's always reaction to that action, that's how serious it is."

It's not clear whether any unintentional damage was caused by these unsanctioned backfires, or if they even did any good. Cal Fire received reports about the activity and says it is investigating "backfires or something of that nature being put into play by individuals not assigned to the incident."

As the Press Democrat reports, these individuals may not have been residents, but in fact part of a private fire brigade hired by a property owner or their insurer to protect a particularly high-value property. This fire was burning, after all, in the heart of some of the most prestigious appellations in the Napa Valley, where vineyard land can be worth $1 million per acre.

Cal Fire hasn't even specified whether the reported backfire activity was in Sonoma or Napa county, or whether such private firefighters were involved. But under the law during a fire emergency, such contract firefighters are not permitted to participate in the firefight or itself by lighting backfires — they are restricted only to clearing defensible space and defending a specific property from harm.

As McLean tells the paper — implying that such hired hands might be to blame — these contractors are supposed to defend whatever property they're there for and then leave the fire zone. "They are not to stay and defend."

It's not clear on which day or days of the fire this activity was occurring — the fire began early on the morning of September 27 in Napa County and spread by evening into Sonoma County.

NBC News covered the controversial topic of these contracted firefighters for the wealthy in 2018, in the wake of the Tubbs and Nuns fires in Sonoma County, and the Atlas Fire in Napa. (It also became a plot point on Apple TV+'s The Morning Show, with a story that Reese Witherspoon's character wanted to cover in Malibu despite the objections of her wealthy boss.) Major insurer AIG apparently pioneered the idea for its most elite clients in fire-prone areas back in 2005, and other companies like Chubb have followed suit with "Wildfire Defense Services" built into some policies.

McLean spoke to the issue to NBC at the time, saying he wasn't aware of any problems being caused by these contracted firefighters. But, he said, "Our primary function is to make sure the public is safe and taken care of. All these other external factors, as they come in, then we have to think about them... They're a help because of the preventative aspects. We can work together, we just need to make sure we do work together."