Firefighter dies in California wildfire, leaving behind pregnant wife

The Thomas fire is the fourth largest in California state history

Firefighters keep an eye on flames as pockets of unburned vegetation flare in the California wildfires (Mike Eliason/Santa Barbara County Fire Department via AP)

A firefighter with a baby on the way was killed while working the California wildfires, authorities have confirmed.

Cory Iverson, a 32-year-old engineer with the California engine strike team in San Diego, died fighting the Thomas wildfire in Ventura County. The blaze is the fourth largest in California history, and has so far burned through 379 square miles (982 square kilometers) of the state.

Officials are investigating the circumstances of Mr Iverson’s death, according to Fire Chief Ken Pimlott of the California Department of Forestry and Fire Protection.

"Anne and I are saddened by Engineer Cory Iverson's tragic death," California Governor Jerry Brown said in a statement. "His bravery and years committed service to the people of California will never be forgotten."

Mr Iverson had been with the state since 2009. He left behind his wife, Ashley, and their 2-year-old daughter. Ms Iverson was pregnant with the couple’s second child, expected this spring.

Dozens of police and fire vehicles escorted the fallen firefighter's hearse to the county medical examiner’s office on Thursday.

“Corey is just a great young man and he was somebody who just really loved his job,” Chief Tony Mecha of the San Diego County Fire Department told CBS. “What really hit all of us today is that normally this time of year we’re supposed to be slowing down and spending time with our families.”

The California wildfires have also claimed the life of Virginia Pesola, a 70-year-old woman who died in a car crash while evacuating a threatened area. About 100,000 people have been evacuated since the fires erupted on 4 December. Authorities said almost 1,000 structures had been destroyed in the blaze, which is larger than New York City.

Firefighters tackling the blaze were working 24- to 36-hour shifts, Santa Barbara County fire spokesman Mike Eliason told CNN. More than 8,000 people are working on the fire-fighting effort, pushing through strong winds and low visibility.

The blaze was about 35 per cent contained by Friday, but Mr Eliason said he expects it to continue burning for weeks.

"Our hearts go out to all the folks who have lost homes already,” Mr Eliason said. “Especially this time of year with the holidays coming, you've got to feel for these folks who've lost just everything.”

He added: "In some cases they had just minutes before they could evacuate and left with just clothes on their backs. We're trying our best to make that not happen anymore."