Simultaneous fires destroyed two vacant buildings at the 129-year-old Rancho Los Amigos Rehabilitation Center campus in Downey early Monday, authorities said.
Firefighters responded to a blaze on the Rancho Los Amigos south campus at 2:28 a.m. and found an abandoned two-story house near Erickson Avenue and Consuelo Street fully engulfed in flames, the Downey Fire Department said in a statement.
As firefighters were trying to put out the fire, another blaze was reported on the campus. More fire crews were called to the scene, and they found a burning 50-by-50-foot commercial building to the southeast, according to the fire department.
The second building was about a block away, NBC-LA reported.
Both buildings were total losses, and the causes of the fires are under investigation, the Fire Department said.
Los Angeles County sheriff's deputies detained four people for questioning about the fire, which authorities said was suspicious, KTLA reported.
The sprawling Rancho Los Amigos campus opened in 1888 as the Los Angeles County Poor Farm, which offered ranch work and medical care to handicapped, ill, elderly and homeless people.
It was eventually renamed Rancho Los Amigos and operated as a hospital for chronic illnesses until the 1950s, when a polio epidemic turned it into a rehabilitation center.
The property's more than 200 acres are split in two by Imperial Highway. The Rancho Los Amigos National Rehabilitation Center, a county-run hospital specializing in spinal injuries and stroke rehabilitation, is on the north side, and several former Poor Farm structures are on the so-called south campus.
In February, a fire ripped through an abandoned building on the south campus near Dahlia Avenue and Consuelo Street.
10:35 a.m. This article was updated with authorities detaining four people.