A woman who was critically wounded in last week's Santa Monica shooting rampage died Sunday, bringing the total number of victims killed by the gunman to five.
Marcela Franco, 26, died of her injuries at Ronald Reagan UCLA Medical Center, according to Santa Monica College spokeswoman Tricia Ramos.
Franco had been a passenger in a Ford Explorer driven by her father, campus groundskeeper Carlos Navarro Franco, 68, who also was killed in Friday's attack.
Investigators trying to determine why the gunman planned the shooting spree were focusing on a deadly act of domestic violence that touched off the mayhem.
The heavily armed man's attack against his own family led to the violence in Santa Monica streets, lasting just a matter of minutes until he was shot to death in a chaotic scene at the college library by police.
Investigators were looking at family connections to find a motive because the killer's father and brother were the first victims, an official briefed on the probe who requested anonymity because he wasn't authorized to speak publicly told The Associated Press.
The killer, who died a day shy of his 24th birthday, was connected to a home that went up in flames after the first shootings, said police Chief Jacqueline Seabrooks. She refused to elaborate or name the suspect because a surviving family member was out of the country and couldn't immediately be notified.
SWAT team officers searched the shooter's mother's Los Angeles apartment and officers interviewed neighbors about the son who lived with her, said Beverly Meadows who lives in the adjoining unit.
Public records show that Meadows' neighbor is Randa Abdou, 54, the ex-wife of Samir Zawahri and former co-owner of the house where the first shooting took place.
Abdou was out of the country visiting relatives and wasn't expected home for another week, Meadows said. It wasn't clear if the son who lived with Abdou was a victim or the suspected gunman.
Zawahri, 55, brought his family to the neighborhood of small homes and apartment buildings tucked up against Interstate 10 in the mid-1990s, according to property records.
Not long after arriving on Yorkshire Avenue, the couple went through a difficult divorce and split custody of their two boys, said Thomas O'Rourke, a neighbor.
When the sons got older, one went to live with his mother while the other stayed with the father.
Standing next to the weapons and ammo found at multiple crime scenes, Seabrooks said at a Saturday news conference that the "cowardly murderer" planned the attack and was capable of firing 1,300 rounds.
The killer had a run-in with police seven years ago, but Seabrooks wouldn't offer more details because he was a juvenile at the time.
The gunman was enrolled at Santa Monica College in 2010, Seabrooks said.
After neighbors watched in shock as he shot at his father's house and it went up in flames, he opened fire on a woman driving by, wounding her, and then carjacked another woman.
He directed her to drive to the college, ordering her stop along the way to shoot at a city bus and people on the street. Two people on the bus were injured.
Police had received multiple 911 calls by the time the mayhem shifted to the college, a two-year school with about 34,000 students located more than a mile inland from the city's famous pier, promenade and expansive, sandy beaches.
On campus, he opened fired on a Ford Explorer driven by Navarro Franco, who plowed through a brick wall into a faculty parking lot.
Joe Orcutt heard gunshots and went to see what happened in the parking lot. He said he saw the Explorer in the brick wall and was looking for the shooter when, suddenly, there he was 30 feet away firing at people like it was target practice.
The gunman then moved on foot across campus, firing away. Students were seen leaping out windows of a classroom building and running for their lives. Others locked themselves behind doors or bolted out of emergency exits.
At some point, he dropped an Adidas duffel bag loaded with ammunition magazines, boxes of bullets and a .44 revolver. Police also found a small cache of ammunition in a room in the burned-out house.
Trena Johnson, who works in the dean's office, heard gunshots and looked out the window and saw a man shoot a woman in the head outside the library.
Surveillance photos showed the gunman in black strolling past a cart of books into the library with an assault-style rifle by his side.
The shooter fired at least 70 rounds in the library. Miraculously, no one was injured until two Santa Monica police officers and a campus cop arrived and took out the shooter.
Associated Press writer Christopher Weber contributed to this story.
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