A tip led Philadelphia investigators to a crumbling, long-abandoned cemetery in Southwest Philadelphia in April 2020, and inside a pried-open family vault dating to 1884, they found the remains of Keith Palumbo, a 36-year-old musician and tattoo artist from Delaware County, Pennsylvania, who had vanished two months earlier. His longtime friend, a member of the Warlocks Motorcycle Club, later pleaded guilty to killing him.
The grim discovery at Mount Moriah Cemetery did not end there. Investigators also unearthed the remains of a second man, 33-year-old David Rossillo Jr., a prospective Warlocks member, in the same crypt. Both deaths have since been prosecuted, with convictions and prison sentences for the killers and guilty pleas from three additional accomplices who helped dispose of the bodies.
The case, reported in detail by Fox News Digital, is now the subject of a new episode of Oxygen's "Philly Homicide," hosted by retired detective Chris McMullin. The episode, titled "Metal and Mayhem," airs May 2, 2026, at 8 p.m. But the facts of the case deserve attention well beyond a television hour. They expose what happens when violent criminal organizations operate in the shadows of a city's neglected corners, and when betrayal, real or imagined, becomes a death sentence inside outlaw gang culture.
Keith Palumbo was a heavy metal guitarist and tattoo artist. In February 2020, he was driving his mother's car with two other men when he received a phone call from Michael DeLuca, a Warlocks member who went by the nickname "Kaos." DeLuca told Palumbo to come to his Southwest Philadelphia home. Palumbo went.
He never came back. His family immediately knew something was wrong.
The Philadelphia Inquirer reported that DeLuca pulled a handgun and pointed it at Palumbo. A witness later told investigators that DeLuca shot Palumbo in the face. That same witness told police DeLuca said he had killed Palumbo and needed help disposing of the body.
Retired detective McMullin told Fox News Digital the case hit him hard from the start. "When I learned that he had gone missing, it just gave me an ominous feeling," McMullin said. A relative of Palumbo's stated he was not a member of the Warlocks, making the betrayal by his supposed best friend all the more stark.
Investigators built the case through cooperating witnesses, physical evidence, and cellphone data. The trail led to Mount Moriah Cemetery, a sprawling burial ground in Southwest Philadelphia that had long since fallen into disrepair.
McMullin described the scene in blunt terms:
"Mount Moriah Cemetery had gone out of business years ago. I've been there. There was a time when I worked part-time in the funeral business and I was there. It's something like out of a post-apocalyptic film when you go there. There are headstones that are knocked over and vines growing all over mausoleums. It's very sad because this was a cemetery where people were laid to rest. Typically, you expect it to be cared for perpetually."
He added that the cemetery was so neglected it had become a dumping ground for stolen cars. "I even say in the episode, if you wanted to hide a body, that's probably a good place to do it," McMullin said.
On April 3, 2020, investigators walking the grounds noticed one crypt that appeared recently disturbed. It was the family vault of Capt. A.H. Cain, who had died in 1884. Inside, they found Palumbo's body, and the remains of David Rossillo Jr., who had been missing far longer. In cases like these, where victims' bodies are concealed for years, the discovery often comes down to a single break.
DNA testing confirmed the identities of both men by August 2020.
DeLuca and fellow Warlocks member Michael DiMauro were arrested in September 2020. Their cases proceeded on separate tracks, but both ended in conviction.
DiMauro was found guilty in 2023 of first-degree murder and abuse of a corpse in the death of Rossillo Jr. Prosecutors said DiMauro shot Rossillo, tied a rope around his neck, and dragged his body to the crypt before prying it open and dumping the remains inside. The New York Post reported that the killing took place at Mount Moriah Cemetery itself in 2017, meaning Rossillo's body had lain hidden for roughly three years before investigators found it. DiMauro was sentenced to life in prison without the possibility of parole.
DeLuca pleaded guilty to third-degree murder in Palumbo's death. He was later sentenced to 15 to 35 years in prison. Three other individuals also pleaded guilty to helping dispose of the victims' bodies, as FOX 29 Philadelphia reported.
Assistant District Attorney Robert Wainwright issued a statement after the case concluded:
"I want to thank now-retired Philadelphia Police Detective Joe Bamberski for his diligent and tireless work on this case. I'm very pleased that we are able to bring some measure of justice and peace to the loved ones of these two victims."
The motive behind Palumbo's murder remains murky. McMullin said investigators never got a clear answer from DeLuca. Authorities and witnesses suggested DeLuca may have suspected Palumbo of cooperating with law enforcement, but no evidence was presented to support that claim.
McMullin offered his own assessment: "It was speculated that he may have done it to set an example not to cross him. This victim was his lifelong best friend. Was he trying to make an example for the other members? It certainly seemed like they were afraid of him."
Retired ATF Special Agent in Charge Bernard Zapor, who spoke to Fox News Digital about outlaw motorcycle gang culture more broadly, described the Warlocks as deliberately low-profile compared to larger organizations. "Some gangs are purposely more low-key," Zapor said. "They're not interested in all the publicity and notoriety."
But the code inside, Zapor explained, is the same everywhere:
"They all have a similarity in that betrayal of the organization is a death sentence. You have allegiance to the club first, and then your family comes after that. It's club before family, club before self. And the suspicion of being an informant is dangerous and unfortunate."
Zapor was even more direct about what that suspicion means in practice: "If you're suspected of being a police informant, the only outcome is death. It's a death sentence if they can get to you." Authorities have long identified the Warlocks as a serious outlaw motorcycle gang and have tied members to violent crimes including murder, assault, and drug trafficking. The pattern of trusted associates turning killer is grimly familiar in cases like these.
McMullin said the Palumbo case left a mark. "All the cases we explore in this series are tragic, but this was such a case of betrayal," he said. He described DeLuca's act as calculated: "I do think that this was calculated and planned. They more than likely took [Palumbo] to the clubhouse with the intention of doing that to him."
He also noted the role fear played among those around DeLuca. "They were all afraid of [DeLuca]," McMullin said. But when it came time to face prosecution, self-preservation won out. "When push came to shove, they didn't want to lie and possibly risk taking a prosecution to protect him," McMullin said. "I just think there's no honor among thieves. Loyalty is something made very clear that's expected. But I also think that people are also out for themselves, especially people who are committing a lot of crimes, heinous crimes at that."
Palumbo's friends and loved ones, including Michael Davvocato, Lierin Buckley, and Matthew Sondermann, sat down for the Oxygen episode to speak about his life and the toll his murder has taken over the years. Retired detectives John Taggart and Joe Bamberski also described how the cold case was built and solved. Stories like this one, where a missing person's loved ones are left waiting for answers, are a reminder that behind every case file is a family in limbo.
McMullin summed up what made this case different from the dozens of homicides he has worked: "There's the relationship between the killer and the victim. Although sadly, more people are killed by people they know than people they don't know. And outlaw biker gangs are notoriously violent. Michael DeLuca, in my opinion, did an evil act."
The recovery and identification of remains can take months or years, but the work of Philadelphia detectives and prosecutors ensured that Palumbo and Rossillo did not stay nameless forever, and that the men responsible did not walk free.
Keith Palumbo's only crime, by all available accounts, was trusting the wrong friend. In the world of outlaw gangs, that trust cost him everything, and the abandoned crypt where his body was hidden says as much about the decay of accountability as it does about the decay of the cemetery itself.
