The body was discovered Friday night near La Palma Avenue and Imperial Highway.
Anaheim police received an assault-in-progress call at 8:15 p.m. Several witnesses reported seeing the attack and a suspect running from the scene. An Anaheim police officer apprehended a suspect blocks from the scene.
Area residents say the victim is well-known and well-liked in the neighborhood and describe him as a Vietnam veteran in his mid 60s who goes by the name of John.
The murder follows three homicides of homeless men in Orange County. Authorities have determined those murders are the work of a serial killer.
In a news conference Friday night at the scene, Anaheim police announced a man that had been detained for questioning was arrested for Friday night's murder. Police would not speculate if the man was suspected in the previous murders. Police did say the suspect matches the description of the serial killer.
Earlier Friday evening, police had focused their attention on drivers near the scene of the third murder, just three miles away from the latest killing.
"Often when people drive through a certain area, almost daily, they tend to know the lay of the land, and if they give us just a little bit of information, we may be able to use that to help in this case," said Anaheim Police Department Sgt. Bob Dunn.
The third victim was found stabbed to death outside a library in Yorba Linda. A homicide task force set up road blocks surrounding the area in hopes someone may have key information in the case.
James McGillivray, 53, was found fatally stabbed Dec. 21 outside a strip mall in Placentia. A week later, 42-year-old transient Lloyd Middaugh was found stabbed to death near the Santa Ana River Trail in Anaheim. Two days after his murder, the bloody body of 57-year-old homeless man Paulus Smit was found next to the Yorba Linda Public Library.
Police handed out fliers Friday with an image of a white sedan captured by a surveillance camera at the scene of the first murder in Placentia. The flier also had a dark and grainy picture of the suspect.
Anyone with information on the case should call the Homicide Task Force at (714) 756-1944.