Authorities said they found the home ransacked and saw the body of Alois Nihsnohl.
Investigators said the man's caretaker made the call.
A homicide investigation was launched when signs of a struggle were found at the home, but officials have not been able to speculate on the cause of death.
"There's no evidence of a break in, no evidence of a robbery, no evidence of a stab wound and no evidence of a gunshot," said LAPD Capt. Anita Ortega. "There was a struggle, so there was some blood involved. However, the coroners haven't been here so it's nothing that's obvious to the investigators or criminalists."
Investigators said he lived alone. His wife died years ago.
"There are some neighbors that are reporting that he was receiving medical treatment for a heart condition, so that may have played a role in it," Ortega said. "At this time, we just don't know."
Neighbors said he was a long-time resident of the community. They described him as being pleasant.
"He pretty much kept to himself," said neighbor Daniel Durazo. "He was just an old man, we'd see him now and then moving his cars and what not. He was kind of quiet."
"When we'd see him he'd say hello, but that was about it," added Amanda Durazo. "He was really quiet."
They said they didn't hear any noise coming from the home Wednesday morning.