This photo of Adan Fabian Perez is provided by the Kentucky Horse Racing Commission ("KHRC"). The photo is from his most recent KHRC license, which is required for anyone who works in the stable area at Churchill Downs. Perez was found dead in a Churchill Downs stable on Sunday, May 6, 2012.
LOUISVILLE, Kentucky (CNN) -- Wilson Perez believes his father's killer is one of the hundreds of stable workers who live and care for horses in an area known as the "backside" of the Churchill Downs horse racing grounds.
"I imagine he's wandering around here," Wilson Perez told CNN during an exclusive interview near the barn where his father's body was found. "It has to be someone who lives here because no one else can come in."
Louisville Police investigators have released few details about the death of 48-year-old Adan Perez. Police say Perez's body was discovered around 5 a.m. Sunday morning by barn workers, just several hours after the final races of Kentucky Derby Day.
The body was left in Barn No. 8, which backs up to the backstretch of the famed Churchill Downs horse racing track.
The "backside" of Churchill Downs is made up of dozens of barns that house more than a thousand horses. It's also where some 600 stable hands live.
It's a secluded and often overlooked world. It's home to the transient workers of the horse racing industry. Most workers are Central American immigrants who move around the country looking for work with stables and trainers.
"The outside world doesn't see this world. They don't know what the backside of the racetrack is like," Churchill Downs chaplain Ken Boehm said. "It does concern us that there's someone back here or there could be someone back here still that could commit such an act."
Police say there are no suspects in the slaying of Adan Perez but are looking into several altercations that occurred at the track.
Wilson Perez said he last heard from his father around 11:30 p.m. Saturday night. Both men talked on the phone for several minutes at the end of a hard day's work during the Kentucky Derby.
"He called me to see how I was doing and where I was," Wilson Perez said.
This was almost a daily routine for both men. Father and son worked in different barns on the Churchill Downs grounds and could go most of the day without seeing each other.
"He told me he was outside (the racing grounds) at a restaurant with friends," Wilson Perez added. "Everything was normal, like every time he called me. He never told me there were any problems."
Wilson Perez said he hasn't heard any stories of his father getting into any altercations the night of the murder. He also said he never heard his father talk of having enemies or having any problems with anyone around the grounds.
Wilson Perez first walked through the gates of Churchill Downs two years ago. He had convinced his father to let him leave home in Guatemala and find work in the barns caring for horses.
Adan Perez worked for horse trainer Cecil Borel, the brother of three-time Kentucky Derby-winning jockey Calvin Borel.
Wilson Perez said he wanted to leave Guatemala to get closer to his father, who had been working in Kentucky since 2008.
"I asked him to bring me here," said Wilson Perez. "I wanted to be with him."
The backside of horse racing tracks is the forgotten side of the horse racing grounds. It's an area that highlights the stark class structure of horse racing. It's where you see millionaire horse owners standing shoulder to shoulder with stable hands who roughly earn between $250 and $800 a week for a variety of jobs caring for the prized horses.
"Such a mash of people back here, the richest of the rich, the poorest of the poor and everyone in between," said Boehm, who ministers to the stable hands.
But it's also a secluded and difficult world for outsiders to penetrate. Workers often move around the country, from horse track to horse track following the work wherever it goes.
Boehm said on any given day there are about 600 people who live on the backside of Churchill Downs. They can live on the grounds for free, but the workday usually starts early. Around 4 a.m. workers start cleaning the stables and feeding horses. Other workers prepare the horses for their daily workouts on the racetrack.
Boehm hoped stable workers who might have information about Adan Perez's slaying won't be reluctant to come forward.
"I'm hoping someone will say something, if not to me, to a trainer or to a friend that they become comfortable with," he said.
Wilson Perez said he still loves the work at Churchill Downs. In fact, since his father's death he's kept working through the pain and anguish even as he makes arrangements to get his father's body sent home to Guatemala for a burial.
Wilson Perez said he doesn't want to return to Guatemala; he wants to keep working at Churchill Downs.
"He was a good father," Wilson Perez said. "Everything he knew; he would pass on to me."