The wildfire that has burned more than 7,000 acres in Yucaipa and surrounding areas was caused by an explosive used during a gender reveal party, according to the California Department of Forestry and Fire Protection. The state agency said the fire started at El Dorado Ranch Park in Yucaipa on Saturday morning, when a smoke-generating pyrotechnic device at the party sparked the flames. The wildfire broke out at 10:23 a.m., spreading to areas further north and triggering mandatory evacuations, officials said. Dubbed the El Dorado Fire, it more than doubled in size Sunday as firefighters grappled with challenging weather conditions...