A series of attacks on homeless men, where the men were attacked with spikes, is not the first time in San Diego history that homeless victims have been attacked in a nearly identical way.
In July, five homeless victims -- three of whom died -- were attacked while sleeping across the San Diego region. Some of the victims were attacked with railroad spikes, according to a Deputy District Attorney.
In what appears to be a bizarre coincidence, it's not the first time in San Diego's history a killer targeted sleeping homeless men using a spike as a murder weapon.
In May 1984, two homeless men were sleeping alone on sidewalk benches in downtown San Diego's Gaslamp area. Both were stabbed, one fatally, with an eight-inch tapered steel spike found impaled in one of the victim's heads, police sources confirm to NBC 7 San Diego.
Both men were sleeping on different benches but near the intersection of Fifth and Island avenues and both were attacked in the early morning hours before dawn.
According to a San Diego Union report, a victim later identified as Eugene Addison staggered into the Rescue Mission, which was located at the 500 block of Fifth Avenue, to get help around 4:45 a.m. The victim sought help immediately after the attack, which he survived, despite being impaled in the head by the object.
Former San Diego Police Officer Dave Walker was working the downtown patrol when the man stumbled to the 500 block of Fifth Avenue with an eight-inch spike driven into his skull.
"When he walked up to my car, I really believed he had his finger stuck in his ear and I was just going to ask him, 'Hey what's the problem?' and then I very rapidly realized there was a metal spike," he recalled.
Minutes later, police found a body lying on the sidewalk near the intersection of Fifth and Island. The victim had an apparent spike wound through his ear. Police identified 29-year-old Mallin Allen Weaver, a transient, as the deceased victim.
Former Homicide Captain Paul Ybarrando said the weapon in the 1984 case ended up being a “marlin spike" and not a “railroad tie," but he called the similarities in the cases “highly unusual.”
Defendant Jon Guerrero, charged in the series of July killings, would have been around seven at the time of the 1984 attacks, making him too young to be considered a suspect in those prior cases, according to police sources.
Guerrero, 39, of San Diego, initially faced three counts of first degree murder, two counts of attempted murder and two counts of arson, but in court last week a judge suspended all criminal proceedings until Guerrero could get a psychological evaluation.
Public Defender Danesh Tandon, who represents Guerrero, said his client has an "extensive" mental health history.
"My client is severely mentally ill and there are going to be further court hearings regarding his ability to stand trial," he said, adding that he could not elaborate.
Three of the Guerrero's victims died from their injuries. Two victims were expected to survive.
Officials found more railroad spikes in Guerrero's backpack and at his apartment, Harvey said.
If charged and convicted, Guerrero faces life in prison without the possibility of parole.
There is also a special circumstance in that more than one homicide occurred in a series, so he could face the death penalty, according to Harvey.
Guerrero is due back in court on Oct. 9 for a competency hearing.
Ybarrando said one victim from the 1984 attacks survived and even worked at one point for the City of San Diego in the police equipment garage. NBC 7 San Diego has been unable to track him down.
The 1984 homicide case was never solved.