A vagrant was arrested about midnight Sunday on suspicion of murdering another transient whose body had been found several hours earlier in the dry bed of the Santa Ana River, police said.
An autopsy Monday showed that the victim, a 52-year-old man who investigators believe had been living in the river bed, died of a head injury, authorities said.
Police Officer Bob Gustafson said the victim's name was being withheld pending notification of relatives.
Jerome George Johnson, 44, who also had been living in the river bed, was arrested several hours later at the scene of the murder and booked into the Orange County Jail on suspicion of murder, Gustafson said.
Gustafson said Johnson was believed to have been an acquaintance of the victim, whose body was found in the river bed about 50 feet north of the Memory Lane bridge at about 4 p.m. Sunday.