Residents say the victim, identified as Rahmatolah "Davey" Yaghoubi, was gardening when he was assaulted around 12:30 p.m. Monday near Falmouth and Catalpa avenues. He later died at the hospital.
Danni Harrower lives a few doors away and says the victim was her friend.
"He was just the sweetest man...He always greeted my child, me and my dogs while we were walking. Gave us figs," she said. "This is just so unwarranted. It's just very sad."
Police believe it was a random attack. Officers searched the area and arrested David Steven Abbott, 30, of Anaheim for the fatal beating after spotting him a few blocks from the crime scene.
Police say Abbott had attacked another man, age 60, just 20 minutes earlier, but the victim in that instance was able to fight the suspect off.
Abbott is being held on $2 million bail.
Investigators also say Abbott had been out on bail for an earlier attack, an assault with a deadly weapon on May 15.
"His incident from the 15th and this incident appear to be random in nature, which means we may never know why he targeted that individual. It does appear to be strictly random," said Anaheim police Sgt. Shane Carringer.
Anyone who has information about Abbott or may have been victimized in a similar assault are being asked to contact detectives at (714) 321-3669 or Orange County Crime Stoppers at 855-TIP-OCCS.