The brush fire at Camp Pendleton that broke out Saturday afternoon has burned more than 2,500 acres and is 20% contained, Marine officials said Sunday night.
Firefighters expect "minimal fire movement" and predict full containment by Tuesday, officials said.
The fire started about 12:45 p.m. Saturday in the Lake O'Neill area of the sprawling base.
Some 230 residents from the O'Neill Heights housing area were evacuated to the Paige Fieldhouse. Patients were transferred to safety from the base hospital that overlooks Lake O'Neill.
Residents were allowed to return to their homes Sunday night. The hospital is now fully operating and patients have returned.
Saturday afternoon, patients at the 61-bed hospital were transferred to Tri-City Medical Center in Oceanside and the Naval Medical Center San Diego after a power outage at the facility 12 miles from the main gate of the base.
The base hospital provides medical care for active-duty personnel and their families. Marines and sailors with major injuries from combat, and others needing advanced, specialized care, are treated at the Naval Medical Center San Diego.
Minor damage was reported to four buildings on the base. A truck parked near the hospital was destroyed. No injuries have been reported.
On Sunday, the fire was battled by 339 firefighters from the Camp Pendleton Fire Department, the U.S. Forest Service and other agencies. They were assisted by five helicopters.
No cause of the blaze has been announced.