Mass murder suspect Elliot Rodger had carefully laid out a plan to take his revenge on the world for being rejected by women at every turn and described in a 137-page rant he left behind how he would lure unsuspecting victims into his apartment and kill them there.

But in the end, Rodger was evidently scorned even as he plotted his deadly spree. Unable to draw anyone into the apartment he shared with two UC Santa Barbara students from San Jose, he turned his deadly gaze on James Cheng-yuan Hong, 20, and George Chen, 19, stabbing them and a third man who was apparently visiting -- Weihan Wang, 20, of Fremont -- in a frenzied attack.

Santa Barbara County Sheriff Bill Brown described what authorities found as "a horrific crime scene," saying the roommates and their visitor had been "repeatedly stabbed," but he did not give any details on how much time elapsed between the stabbings and the subsequent shooting spree, in which Rodger slaughtered three more victims -- including two women at a UCSB sorority house he had identified as the school's "hottest" -- injured 13, and then, according to a sheriff's statement, died from an apparent self-inflicted gunshot to the head.

Hong and Chen were listed as tenants on the lease for the apartment, along with Rodger. Investigators were still in the process Sunday of determining whether Wang was also a roommate or was visiting. The manager of the Capri Apartments said in a statement that only two of the men were residents.

All three victims were identified as UC Santa Barbara students. According to their Facebook pages, Hong was a 2012 graduate of Lynbrook High School and was studying computer engineering. Chen graduated the same year from Leland High and had been a camp counselor for the YMCA. Wang was briefly a student at American High School in Fremont before he transferred to a private school, according to James Morris, superintendent of the Fremont Unified School District.

According to an unconfirmed report that quoted "family friends," at least one of the murdered men was just days from moving out of the apartment. The sheriff revealed during a news conference Saturday that in January, Rodger accused Hong of stealing $22 worth of candles from him. Rodger took the unusual step of making a citizen's arrest for petty theft and contacted sheriff's deputies, who arrested Hong. He was booked and released, but the two men evidently continued living together.

Sheriff's investigators said they believed Rodger killed those three victims before going on a shooting rampage in Isla Vista around 9:25 p.m. on Friday. The latter part of the attacks involved Rodger using his BMW as a battering ram against an Alamo man who was cruising on a skateboard -- breaking both his legs.

Nick Pasichuke, a water polo player at University of the Pacific in Stockton, was recovering Sunday in a Santa Barbara hospital, hours after having surgery to repair two major bone breaks in his left leg that required the insertion of rods. Jill Pasichuke said her son also suffered some facial fractures, which will not require surgery, and some road rash.

The overwhelming horror wrought by the carnage was even more difficult to fathom in view of terrifying threats of suicide and violence that were captured in Rodger's online videos. In one, he stares icily into the camera, despairs over his hollow romantic life, then delivers a dark promise: "That's a problem that I intend to rectify. I, in all my magnificence and power, I will not let this fly."

His parents said they were so concerned that they called police. Officers who showed up at Rodger's doorstep for a mental health check in April, however, found a well-mannered, if shy, young man who they concluded posed no risk.

"System failed"

One major question that will have to be confronted in the aftermath of the murders is why authorities had not seen the videos. By the time law enforcement viewed them, it was too late: Rodger had gone on his deadly rampage. The Sheriff's Office "was not aware of any videos until after the shooting rampage occurred," Santa Barbara County Sheriff's Office spokeswoman Kelly Hoover said.

Brown has defended the officers' actions, but the case highlights the challenges that police face in assessing the mental health of adults, particularly those with no history of violent breakdowns, institutionalizations or serious crimes.

"Obviously, looking back on this, it's a very tragic situation, and we certainly wish that we could turn the clock back and maybe change some things," Brown told CBS' "Face the Nation" on Sunday.

"At the time deputies interacted with him, he was able to convince them that he was OK," he said.

Attorney Alan Shifman said the Rodger family had called police after being alarmed by YouTube videos "regarding suicide and the killing of people" that Elliot Rodger had been posting.

Doris A. Fuller, executive director of the Virginia-based Treatment Advocacy Center, said California law has provisions that permit emergency psychiatric evaluations of individuals who pose a serious threat, but that was never triggered.

Rodger's family has disclosed their son was under the care of therapists.

"Once again, we are grieving over deaths and devastation caused by a young man who was sending up red flags for danger that failed to produce intervention in time to avert tragedy," Fuller said in a statement.

"In this case, the red flags were so big the killer's parents had called police ... and yet the system failed," she said.

Alamo survivor

As authorities tried to piece together clues to what set off Rodger's rampage, the victims' families were also picking up the pieces of their shattered lives. "It's been just painful to watch," Jill Pasichuke said as she watched over her son Nick.

In a quiet, somber voice, the shaken mother described how she and her husband received a phone call around 10:30 p.m. Friday informing them that Nick had been seriously injured.

Nick Pasichuke was visiting his best friend -- Tyler Martin -- from San Ramon Valley High. The two were with a couple of young women headed back to Martin's apartment from Freebirds World Burrito.

"The girls glanced back, and (the driver) just gunned it," Jill Pasichuke said.

She was told her son was probably thrown about 50 feet off the long board-style skateboard he was riding.

The women were crying; Martin stayed with Nick and talked to him to keep him from going into shock. It took 45 minutes for an ambulance to show up, which Jill Pasichuke said is understandable given what else was happening.

"I just jumped in the car and headed down there," she said. "My husband stayed and held down the fort and fed me information."

She arrived around 4 a.m., not knowing what to expect.

Nick Pasichuke is already showing signs of progress, even asking nurses when he can start playing water polo again. He's supposed to start a lifeguard job and water polo training in a few weeks, his mother said.

Mercury News staff writers Sharon Noguchi and Joe Rodriguez and the Associated Press contributed to this report.