After burning throughout wide swaths of Southern California since December 4, the US Forest Service announced that the largest fire in California’s modern history is now 100% contained.

The Thomas Fire, which began in the hills above Los Angeles and quickly engulfed sections of Ventura and Santa Barbara counties, has burned roughly 281,900 acres in the space of a month. That size is the equivalent of more than Dallas and Miami combined, according to officials.

News that the largest wildfire on record in California was declared contained came Friday, days after mud on the coastal mountain slopes it scorched came sliding down onto vulnerable homes during a storm, killing at least 18 people.

The cause of the fire remains unknown. But it was fueled by strong Santa Ana winds and by extremely dry weather conditions this fall and winter, according to the Forest Service.

The service further noted that 1,063 structures were destroyed and another 280 were damaged.

Cory Iverson, a 32-year-old firefighter with the California Department of Forestry and Fire Protection, or Cal Fire, died last month while battling the Thomas Fire, according to a report in NBC News.

At one point, more than 2,800 firefighters were working to contain the fire. About $177 million was spent fighting the fire as of December 24, according to Cal Fire.

“Los Padres National Forest would like to thank all the first responders and cooperators that responded to this incident over the last month and giving up the opportunity to spend the holidays with their families and the sacrifices they made,” the Forest Service said in a statement Friday. “We would also like to thank the local and surrounding communities for their understanding and support during this time.”

Last year turned out to be the costliest year for wildfires in US history, according NBC, which reported $10 billion in damage.

The wildfire’s devastation greatly contributed to this week’s mudslides in the Montecito area that killed 18 people and destroyed dozens of homes.

“All these hills normally have a protective cover of chaparral,” said Tom Fayram, Santa Barbara’s deputy director of public works. “That’s all gone. Almost 100% gone.”