A firefighter has died while battling a California blaze that was sparked by a “smoke-generating pyrotechnic device” at a gender-reveal celebration. The San Bernardino National Forest Service said in a statement Friday that the firefighter died on Thursday in the El Dorado Fire, which has already torched over 21,000 acres. “The name is being withheld pending notification of next of kin,” a statement said. “Our deepest sympathies are with the family, friends and fellow firefighters during this time.” The El Dorado Fire, which ignited over Labor Day weekend in Yucaipa’s El Dorado Ranch Park, was about 66 percent contained as of Friday morning. The couple that set off the device has been cooperating with officials.