A man with a criminal record and history of mental illness was charged Tuesday with a string of deadly attacks on sleeping homeless men in San Diego, two of whom were set on fire.

Jon David Guerrero, 39 received a two-week extension on how to plea to charges of murder and attempted murder, a delay that ensured many questions would remain a mystery.

Prosecutors did not provide information about a motive or weapons used in the attacks after Guerrero agreed to be held without bail for two weeks, meaning the prosecutors didn't have to disclose details about the crimes to justify his incarceration.

Court records show Guerrero is diagnosed with schizophrenia and has a history of arrests and mental competency hearings, including one judge's order that sent him to a state hospital for treatment.

Dan Tandon, his court-appointed attorney, read a short statement that yielded little insight into his possible defense strategy. He declined to answer questions from reporters about Guerrero.

"San Diego deserves to know the truth and the whole story in this case, and this story begins before July 3 -- years before the first loss of life in this case," Tandon said. "We've already seen there are many twists and turns that a case like this can take."

Anthony Padgett, a homeless man who had been identified as the sole suspect, was released from jail last week after investigators decided they didn't have enough evidence. Padgett bore resemblance to the suspect captured on convenience-store surveillance video and had been convicted in 2010 for setting a sleeping man on fire.

Four days later, Guerrero was arrested by police who heard a homeless man screaming after he was attacked.

Guerrero faces a maximum penalty of life in prison without parole if convicted and may be eligible for the death penalty, said Mackenzie Harvey, a San Diego County deputy district attorney.

The violence began July 3, when police found the badly burned remains of Angelo De Nardo between Interstate 5 and train tracks. The 53-year-old died before his body was set on fire.

The next day, officers responding to a 911 call found Manuel Mason, 61, with life-threatening injuries to his upper torso. A few hours later, police discovered the body of Shawn Longley, 41, who bled from the upper torso and died.

Dionicio Derek Vahidy, 23, died last week at a hospital, four days after he was set on fire downtown. A witness pulled away a burning cloth that the attacker put on him before fleeing.

Two others wounded in the attacks spanning 13 days were expected to survive, though investigators have not yet spoken with them, Harvey said.