By CBSLA Staff

IRVINE (CBSLA) – Firefighters continued to make headway against the Silverado Fire burning just east of Irvine as all evacuation orders were lifted Thursday morning.

A helicopter takes water from the Oso Lake Scout Camp in Rancho Santa Margarita to drop on the Silverado Fire in Whiting Ranch in Lake Forest on Oct. 27, 2020. (Allen J. Schaben/Los Angeles Times/Getty Images)

The Silverado Fire has burned 13,390 acres and is 40% contained as of 8 a.m. Thursday. No homes have been destroyed.

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Two firefighters who were critically burned Monday while battling the blaze are still hospitalized at the OC Global Medical Center in Santa Ana. They remain in critical condition Thursday. Both had at one point been placed on ventilators.

In a news briefing late Thursday morning, Orange County Fire Authority Chief Brian Fennessy said the two firefighters are “fighting for their lives.”

At the fire’s height, more than 91,000 people were evacuated. All those orders were lifted Thursday morning, however.

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About 1,200 firefighters are still battling the fire with the help of five water-dropping helicopters.

“Firefighters worked through the night mopping up and bolstering control lines,” CAL Fire said in a news release Thursday. “Crews will take advantage of favorable conditions today to build additional line, mop up and patrol the fire perimeter.”

The fire broke out before 7 a.m. Monday in the area of Santiago Canyon and Silverado Canyon roads amid powerful Santa Ana winds and red flag conditions. It jumped the 241 Freeway and began spreading west. Within about three hours it had exploded to 2,000 acres.

While the cause remains unknown, Southern California Edison has sent a letter to California regulators stating that a “lashing wire” may have potentially sparked the fire.

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Meanwhile, the Blue Ridge Fire  — which sparked Monday in Corona and then spread west into Chino Hills and Yorba Linda — has burned 14,334 acres and was 30% contained. All evacuation orders for that fire were lifted Wednesday. One home was destroyed and seven more were damaged.