Authorities responded to the Bellington Plaza Apartments on 6th and Wall streets at about 6:45 a.m. Police say a resident told the manager there was a foul odor coming from the apartment, and the manager went inside and found the body.
Investigators say the victim had been dead for several days. He died of blunt force trauma, police said.
The apartment building is run by Volunteers of America.
Anyone with information is urged to call the LAPD at (877) LAPD-24-7.