Seven people were killed, including the suspect, identified as 22-year-old Elliot Rodger, and 13 others were wounded, four by the suspect's vehicle.
Of the six victims, three unidentified males were found stabbed to death in Rodger's apartment. Three other people were shot and killed.
The apartment was one of several crime scenes identified by the sheriff's department.
The shooting began outside the Alpha Phi sorority house, where 22-year-old Katherine Cooper and 19-year-old Veronika Weiss were killed. Another woman was left with multiple gunshot wounds.
Authorities said Rodger then went to a nearby deli, where he shot and killed 20-year-old Christopher Michaels-Martinez.
The rampage continued when Rodger wounded eight people as he fired rounds at the sidewalk, and struck four people with his black BMW, the sheriff's department said. One person had a minor injury from an unknown cause.
Rodger eventually collided with parked cars. Deputies caught up with Rodger, removed him from the vehicle and handcuffed him. He was dead from a gunshot wound to his head. The sheriff's department said it appears Rodger took his own life.
Authorities recovered three 9MM handguns from Rodger's vehicle. Two are semi-automatic Sig Sauers with 34 loaded 10 round magazines. A glock with 10 loaded 10 round magazines was also found. The guns are registered to Rodger and were legally purchased in Goleta, Oxnard and Burbank.
Seven victims remain in the trauma center at Santa Barbara Cottage Hospital. Two patients are in good condition, three are in fair condition and two are in serious condition.
Four patients in the shooting have been treated and released from a separate hospital.
Elliot Rodger is the son of Peter Rodger, an assistant director on "The Hunger Games." Peter Rodger confirmed Saturday morning through his attorney, Alan Schifman, that his son was the gunman. Schifman says that the family has not yet seen his body, but they have been told their son was killed and believe he killed six people.
Rodger, of Woodland Hills, was a Santa Barbara City College student who was living in Isla Vista.
A 137-page document believed to have been written by Rodger called titled "My Twisted World." It details intentions for a "Day of Retribution."
"It would be a day in which I exact my ultimate retribution and revenge on all of the hedonistic scum who enjoyed lives of pleasure that they don't deserve. If I can't have it, I will destroy it. I will destroy all women because I can never have them."
It's a document the Santa Barbara Sheriff's Department is very much aware of. The Santa Barbara County Sheriff's Department said the rampage was "the work of a mad man."
"We have obtained and we are currently analyzing both written and videotaped evidence that suggest that this atrocity was a premeditated mass murder," Santa Barbara County Sheriff Bill Brown said.
"There's going to be a lot more information that will come out that will give a clearer picture of just how disturbed this individual was," he added.
Brown said that a disturbing YouTube video, posted hours before the shooting, appeared to be linked to the rampage.
In the video, Rodger sits in the driver's seat of a car as he promises "retribution" and discusses his "loneliness, rejection and unfulfilled desires." He claims to be a virgin at 22 who was rejected for years, and explicitly describes his plans to shoot women.
"Girls gave their affection and sex and love to other men but never to me," he says, adding that it'll be his last video.
"I'll take to the streets of Isla Vista and slay every single person I see there. All those popular kids who live such lives of hedonistic pleasure while I've had to rot in loneliness for all these years. They've all looked down upon me every time I tried to go out and join them," he says. "They've all treated me like a mouse, well now, I will be a god compared to you."
Concerns expressed over gunman's well-being
Schifman said that in recent weeks Rodger's parents had become concerned over their son's well-being. They contacted police after being alarmed by YouTube videos "regarding suicide and the killing of people." Police interviewed Rodger and found him to be "perfectly polite, kind and wonderful human," Schifman said.
He added that police did not find a history of guns, but did say the man had trouble making friends. A social worker, who worked with Rodger, also contacted police about his alarming character last week.
Rodger, a student at Santa Barbara City College, was described by Schifman as a loner who had trouble making friends. He was allegedly diagnosed at an early age with highly functional Asperger's syndrome and was being treated by multiple professionals.
The shootings broke out in the affluent Isla Vista neighborhood near the University of California, Santa Barbara campus around 9:30 p.m. Friday.
The Santa Barbara County Sheriff's Department says it received multiple 911 calls of a suspect opening fire at random. Sheriff's deputies responded and found several victims suffering from gunshot wounds.
As deputies were assisting the injured in the first round of shootings, reports of gunfire in other areas of the college neighborhood were reported.
Witness recalls chaotic scene
A visibly shaken student told ABC affiliate KEYT-TV that she was approached by the driver of a black BMW who flashed a handgun and asked "Hey, what's up?" Sienna Schwartz said she thought he was carrying an air soft gun and kept walking. She said seconds later, she felt something buzz by her head and quickly realized they were bullets.
"He lifted up a little black pistol, and I just thought it was like an air soft gun or something," she said. "I turned around and started walking the other way. He shot and I just felt the wind pass right by my face."
Isla Vista is home to 23,000 people. The area, located next to the UCSB campus, has a reputation for excessive partying and is filled with restaurants, cafes and bars.
The University of California, Santa Barbara released a statement Saturday morning addressing the shooting.
"Our campus community is shocked and saddened by the events that occurred last night in the nearby community of Isla Vista. Our thoughts and prayers are with the victims and their families who are grieving and mourning as a result of this tragedy," read the statement.
The university did not say if any of the victims were involved with the school.
Gov. Edmund G. Brown Jr. issued the following statement Saturday regarding the shooting: "Anne and I were saddened to learn of this senseless tragedy. Our thoughts and prayers go out to those mourning the loss of their loved ones during this difficult time."
The investigation is ongoing. The Santa Barbara County Sheriff's Office is being assisted by the UCSB Police Department, the California Highway Patrol, the Santa Barbara Police Department, investigators from the Santa Barbara County District Attorney's Office, California State Parks and criminalists from the Department of Justice crime lab.
Anyone with any information was urged to contact the Santa Barbara County Sheriff's Tip Line at (805) 681-4171.
The Associated Press and ABC News contributed to this report.