The latest hotspot in the fight to tame a series of devastating Southern California wildfires is centered in the San Bernardino mountain range (search), where firefighters struggled desperately Wednesday to save emptied-out resort towns as 200-foot walls of flame engulfed dead and dried-out trees.
In San Diego County (search), the state's largest fire claimed another victim when a firefighting crew was overcome by flames, killing Steven Rucker, 38, and injuring three others.
It marked the first firefighter death since the series of blazes began last week.
"It just swept right over them. They probably didn't have time to get out of the way," San Diego County Sheriff's Sgt. Conrad Grayson said.
The death toll later reached 20 after authorities said two people were found dead Wednesday on an Indian reservation as the result of the same San Diego County fire.
• Photo Essay: Ring of Fire Surrounds Southern California
In the San Bernardino Mountains east of Los Angeles, the hot, dry Santa Ana (search) winds from the desert that had been whipping the fires into raging infernos eased Wednesday. But they gave way to stiff breezes off the ocean that pushed the flames up the canyon walls around evacuated mountain enclaves like Lake Arrowhead and Big Bear -- towns that are among Southern California's most popular mountain playgrounds.
By early afternoon, homes were burning in the mountain community of CedarPines Park. The flames were expected to hit the town of Running Springs after crews weren't able to set backfires along a highway to protect the town. The fires also swept over mountain tops, forcing evacuations in parts of the high desert town of Hesperia.
"There's fire on so many fronts, it's not even manageable at this point," said Chris Cade, a fire prevention technician with the U.S. Forest Service, as he watched a pillar of smoke he estimated at 9,000 feet rise into a hazy sky thick with ash. "I am at a loss what you can do about it."
The fires have burned more than 660,000 acres and destroyed 2,600 homes. More than 12,000 firefighters and support crew were fighting what Gov. Gray Davis said may be the worst and costliest disaster California has ever faced. He estimated the cost at $2 billion so far.
The fires burned in a broken arc across Southern California, from Ventura County east to Los Angeles County and the San Bernardino Mountains and south to San Diego County.
"It doesn't look good," San Bernardino Fire Capt. Greg Sears told Fox News.
About 100 fire engines encircled the historic mining town of Julian in the mountains of eastern San Diego County, hoping to save the popular weekend getaway community renowned for its vineyards and apple orchards.
However, some two dozen engines and water tenders that were headed to Julian were forced to turn back when flames swept over a highway. And as the winds picked up, floating embers sparked spot fires near the region of 3,500, forcing some crews to retreat.
South of Julian, about 90 percent of the homes had been destroyed in Cuyamaca, a lakeside town of about 160 residents. Charred cows lay by the side of the road and houses were reduced to little more than stone entryways.
"Everything's kind of happening all at once. These fires are trying really hard to tie in with each other," said Bill Bourbeau, a forest safety officer for the Cleveland National Forest. "It's tremendous."
San Diego County fire officials feared a 250,000-acre fire and the 50,000-acre blaze would merge into a huge, single blaze that would make it nearly impossible to keep it from reaching Julian. The firefighting death and injuries occurred in the larger of the two blazes
Officials in San Diego County -- where most of the deaths took place -- predicted the death toll would rise after investigators began scouring devastated neighborhoods.
A crew of U.S. Forest Service Hot Shots outside Julian was given an ominous warning by their team leader: If they came across any human remains, they were to cordon off the area until a medical examiner could get in.
"If we find somebody in the brush who took off running or whatever," Capt. Fred Brewster told his 19-member team. "Who knows what you're going to find up there? It's a giant mess."
In the San Bernardinos, the cool, moist ocean breezes confounded firefighters, just as the desert winds did over the weekend. Heavy winds kept aircraft grounded in the area, and winds gusting to 60 mph pushed flames up from the mountain slopes into the dense forest.
"They turned around with the wind and the fuel and basically overran us," San Bernardino County Fire Division Chief Mike Conrad said.
Firefighters feared that the narrow roads and sheer number of dead trees, ravaged by drought and a bark beetle infestation, could make it impossible to protect some of the smaller communities in the area.
"It would be suicide to put anyone in there," Conrad said.
Some 80,000 full-time residents of the San Bernardinos have cleared out since the weekend, thousands of them winding their way in bumper-to-bumper traffic out a narrow highway.
A steady stream of vehicles loaded with couches, televisions and other household items inched down the mountain Wednesday.
Others defied the warnings of firefighters and decided to stay to protect their homes.
"I'm afraid, but I've got a lot of faith," said Chrisann Maurer, as she watered down her yard and home amid smoke-filled winds. "I just think there is enough people praying that we might be safe."
Mark Peterson, a firefighter with the Big Bear Lake Fire Department, said the fire was moving toward Big Bear rapidly and called those who refused to leave "crazy."
California Forestry Department incident commander John Hawkins told exhausted firefighters not to give up.
"We hear losses," he said. "But the bottom line is we don't hear how many were saved, how many of you put your name, your body, your heart on the line to save the houses."
Across the border in Mexico, wildfires kept students home from school Wednesday in Baja California, but officials said the threat from fires appeared to be easing. The Mexico fires earlier killed two people and destroyed several homes.
In Colorado, wind-whipped wildfires north and south of Denver on Wednesday forced thousands of families to flee.
A fire in the foothills northwest of Boulder exploded to 3,500 acres, burning an unknown number of structures. A few hours later, a fast-moving fire swept through pine-covered hills in the suburbs of far south Denver, destroying two homes. Evacuations of some 3,000 homes and businesses were ordered. The fire covered 300 acres.
Authorities said they believed both fires were started by power lines downed by high wind.
On Tuesday, arson investigators circulated a sketch of a man who was seen with another man throwing flaming objects from a van in the area of the so-called Old Fire in San Bernardino County.
"Currently we're pursuing two of the fires as possible arson," Chris Parker, the lead arson investigator from the California Department of Forestry, told Fox News.
The Associated Press contributed to this report.