On Tuesday, there were some candles to mark the spot where 38-year-old Omar Santas was gunned down.
As friends drop off candles at the scene of the murder, they said Santas lived just a few feet away from where he was shot.
"It's very shocking and nothing has ever happened like this," said the victim's friend, Deborah Bowers. "You know, never in a million years did I think it would happen to him. No enemies. He's not gang related. Nothing."
Sheriff's detectives worked through the night piecing together what happened.
"Homicide detectives were dispatched to the 15000 block of Gale Avenue in Hacienda Heights," said sheriff's Sgt. Mike Thomas. "A male Hispanic adult was found shot there and he was pronounced dead at the scene."
According to some of the people who live near the alley, the area is fairly busy, but mostly with foot traffic.
"Very rarely do you see any kind of criminal element or anything like that," said neighbor Moses Lomeli. "You have a lot of families taking the short cut to the store or something. Nothing too dangerous."
"I walk my dog everyday and I always feel very safe," said neighbor Grace Garcia. "To have something like this happen in your own backyard, it's very unnerving."
Garcia said her neighbor heard a gunshot Monday night.
The victim, according to friends, was the father of three. One friend said their families went camping two weeks ago and had a great time. He said he spoke to Santas around 8 p.m. Monday, one hour before he was shot and killed.
Anyone with information on the killing is asked to contact the Los Angeles sheriff's homicide detectives at (323) 890-5500.