Before Elliot Rodger took off on a shooting rampage Friday in a college community near Santa Barbara, California, officials say he stabbed and killed his roommates.
Those men - among the six people killed in total - were identified Sunday as Cheng Yuan Hong, 20, George Chen, 19, and Weihan Wang, 20.
All three were students at the University of California, Santa Barbara, and were found dead in Rodger's apartment with multiple stab wounds, officials said.
Hong and Chen are listed on the lease along with Rodger. It was not immediately clear whether Wang was visiting or was another roommate.
A law enforcement source said the third victim in the apartment was a visitor, adding that authorities are working on a theory that the attack happened as the three men were asleep.
Katherine Cooper, 22, and Veronika Weiss, 19, also students at UCSB, were later killed outside a sorority, while Christopher Martinez, 20, was killed at a deli, officials said.
Rodger, the son of a Hollywood movie director, also injured 13 people and died of an apparent self-inflicted gunshot wound, according to police.
Martinez's father gave a wrenching statement to the news media Saturday afternoon. He was "a really great kid" whose "death has left our family lost and broken," Richard Martinez said.
"Our family has a message for every parent out there: You don't think it will happen to your child until it does," the visibly emotional parent said, his voice rising to a shout in obvious agony.
"Why did Chris die? Chris died because of craven, irresponsible politicians and the (National Rifle Association). They talk about gun rights - what about Chris' right to live?" he continued. "When will this insanity stop? When will enough people say stop this madness, we don't have to live like this? Too many have died. We should say to ourselves - not one more."
The comment touched a nerve among many Americans, and it prompted the Brady Campaign to Prevent Gun Violence's president to say the grieving father "got it exactly right."
"It is time for the American public to know the truth about why people are dying every day and, thanks to Americans like Mr. Martinez, that truth is starting to be heard," Dan Gross said in a statement Sunday.
Jeff Dolphin, Christopher Martinez's former roommate, remembered how his friend had always been there for him, the Los Angeles Times reported.
A second-year student at UCSB, Dolphin recalled living with Martinez during their freshman year, the newspaper said.
"Chris was just an amazing guy," he told the Times. "If I was going through something, he was always there for me. If I needed something, he was there. If I needed a textbook, if I was locked out of the room because I forgot my key, he would stop playing basketball or doing what he was doing to unlock the door so I didn't have to get charged. He was just a great guy."
Lyssa Hopper, a 19-year-old student, was at the counter of the I.V. Deli Mart, Hopper told the newspaper. When shooting began, Hopper dropped to the floor, looked up and saw Martinez lying near the door.
"He was slumped over, and he was bleeding," Hopper told the newspaper.
Messages across social media urged that the victims' names remain in the headlines to honor and remember them as more emerges about their alleged killer.
Flowers and cards are being left at the deli. One with a large red heart read, "We will miss you, Chris." Bunches of flowers were wedged into holes left by bullets in the glass storefront.
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