Man used railroad spikes and hammer in attacks on homeless in San Diego, prosecutor says

The case against the man accused of killing three homeless men and critically injuring two others was put on hold Tuesday so his mental state could be evaluated. A prosecutor also revealed for the first time that Jon Guerrero, 39, allegedly used a railroad spike and hammer to attack all five of his victims.

Guerrero, who was arrested July 15 in a string of attacks that started nearly two weeks earlier, faces murder, attempted murder and arson charges.

Deputy Public Defender Dan Tandon on Tuesday asked the judge to suspend criminal proceedings so that a court-appointed psychiatrist could determine whether Guerrero is mentally competent to stand trial.

“My client is severely mentally ill,” Tandon said.

Jon Guerrero’s arraignment is suspended at the request of his defense attorney Dan Tandon, who claims Guerrero is mentally ill. The judge requested the defendant’s face not be shown.

(David Brooks / San Diego Union-Tribune )

But Deputy Dist. Atty. Makenzie Harvey argued that the way the crimes were carried out — and Guerrero’s interaction with authorities after his arrest — suggested he has the ability to understand the proceedings and assist his attorney.

“During this series of crimes, the defendant demonstrated extreme planning and sophistication,” Harvey said. “He selected homeless victims and, in each of the cases, the victims were sleeping.... The defendant attacked the victims with the same method and the same weapon.”

Harvey said an autopsy of the first victim, Angelo De Nardo — who was found July 3 under a freeway bridge — revealed a railroad spike had been driven into the 53-year-old’s head and chest. He was then set on fire.

The second victim, Manuel Nunez Mason, was found critically injured in the Midway District on July 4. A railroad spike had been driven into his sinus cavity, blinding him, Harvey said.

Shawn Mitchell Longley, found dead in Ocean Beach on July 4; Derek Vahidy, who died of injuries suffered July 6; and a final victim, found bloodied July 15, apparently all were injured by railroad spikes found near the crime scenes, Harvey said.

When officers arrested Guerrero, they found a mallet and railroad spikes in his backpack, authorities said, along with the identification of two of the victims. Later, a bucket that contained rocks, railroad ties and more spikes was found in his downtown apartment.

As the two lawyers argued their points, Guerrero tilted his body to the right while holding his right ear. At one point he loudly stated, “Six years!”

According to court records, Guerrero’s mental illness emerged “in full force” around age 22.

He was diagnosed with schizophrenia and considered disabled. At one point he was receiving monthly injections of Haldol, an antipsychotic medication.

In 2009, Guerrero was arrested and pleaded guilty to robbery for repeatedly knocking down a homeless woman and stealing her bicycle. He was placed on probation and found not mentally competent. He then spent time in Patton State Hospital.

lyndsay.winkley@sduniontribune.com

Winkley writes for the San Diego Union-Tribune