A firefighters has died in the California wildfires.

A Firefighter Has Died While Battling A Wildfire Started By A Gender Reveal Party

In an unfortunate turn of events, a firefighter has died while battling the wildfire in Yucaipa, California that was started by a gender reveal party over Labor Day weekend.

USDA Forest Service officials confirmed in a statement on Friday that an unidentified firefighter located at the San Bernardino National Forest died on Sept. 17 while battling the El Dorado Fire. "The name is being withheld pending notification of next of kin," the statement read. "Our deepest sympathies are with the family, friends and fellow firefighters during this time."

The USDA Forest Service that the cause of death "is under investigation" and "more details will be made available as they are confirmed."

According to California's Department of Forestry and Fire Protection, 18,500 firefighters have been battling 27 major wildfires since Aug. 15. More than 5,500 structures have been destroyed since then, and the death of this firefighter brings the number of fatalities to 26 people.

The El Dorado Fire was inadvertently started on Sept. 5 by a California couple using a colored smoke-generated pyrotechnic device to reveal the sex of their unborn baby at El Dorado Ranch Park in Yucaipa, around 70 miles outside Los Angeles. The device was set off in a field but ignited some dry grass, as ABC News reported, and despite the fact that the couple tried to douse the fire with water bottles it quickly got out of control.

That initial fire has spread to more than 21,000 acres of property and after weeks of efforts by firefighters is now approximately 66% contained, according to an incident report. To date, the El Dorado fire has cost $16.5 million, according to the most recent situation report from the National Interagency Coordination Center.

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Fires have been raging through California, Washington, and Oregon, forcing hundreds of thousands of people to flee their homes.

The couple who started the fire have not been identified, but San Bernardino County District Attorney Jason Anderson told ABC News shortly after the fire started that criminal charges could potentially be laid against them. "If investigative reports are filed with our office, we will review all facts, evidence, statements, and reports to determine what criminal charges, if any, need to be filed," Anderson told the news outlet.

Since the death of the firefighter on Thursday, Capt. Bennet Milloy of the California Department of Forestry and Fire Protection told The New York Times that he had not spoken to the family from the gender reveal party but, "personally, I can only imagine how terrible they have to feel for a lot of reasons.”