San Diego ? Flames continued to march through neighborhoods near San Diego and San Bernardino on Wednesday, killing one San Francisco Bay Area firefighter and critically injuring three others as angry residents criticized how the Southern California firestorms have been fought.

It was the first firefighting death since the series of blazes began last week and brought the total number of dead to 20. By Wednesday, fire had consumed 621,000 acres and destroyed more than 2,100 homes.

In the mountains above San Bernardino, near the resorts of Lake Arrowhead and Big Bear, more than 75,000 people have been evacuated. Hundreds of families are filling an emergency shelter set up in a vast airplane hangar at the San Bernardino airport.

In San Diego, crews set up a ring of fire trucks around the historic town of Julian, the flame’s next target, as residents waited to see if two huge fires would merge. Some in San Diego are asking if state fire officials have done enough to help them, but firefighters say that they are exhausted and that more help from other states won’t arrive in time.

A cool, marine air finally pushed inland Wednesday, but the desperately awaited change in weather only compounded problems for firefighters battling the state’s worst infernos ever. The conflagrations took a deadly turn when a firefighter from Novato, Steven Rucker, 38, was killed and three crew members were burned when flames engulfed them outside Julian.

Dozens of communities that thought they had escaped the inferno’s rage that had consumed an area roughly the size of Rhode Island were now at risk, as fire entered Lake Arrowhead in the San Bernardino mountains and approached Julian, where 100 fire engines encircled the historic mining town.

Tired crews were pulled off some contained lines in San Diego Tuesday, with no replacements immediately available. The lack of manpower drew the wrath of residents who had lost their homes, and officials who say Gov. Gray Davis was slow to order aid from outside the state.

A firefighter battles a wildfire in the back yard of a home in the Stevenson Ranch area near Santa Clarita, Calif., attempting to save nearby homes. The death toll in the wildfires increased to 20 on Wednesday.