OAKLAND (CBS SF) -- A manhunt was underway Monday for a knife-wielding killer who fatally stabbed one woman and severely injured her sister as they stepped off a late-night train at Oakland's MacArthur BART station.
The sisters' father -- Ansar Muhammed -- rushed to the BART station Sunday night after he got word of the stabbing.
"I want justice for my daughter. I work at Highland Hospital and I see this every single day," he said with anger in his voice. "I never imagined myself going through nothing like this. That's my baby girl up there."
Jerri Martin, cousin of the two stabbing victims, told KPIX 5 that three Wilson sisters -- Nishiya, Nia and Latifa -- were riding BART last night and were disembarking when they were attacked. She said 18-year-old Nia and 25-year-old Latifa were helping a woman with a stroller get off the train when the attacker came out of nowhere.
Nishiya told family members that -- "They were helping a lady with a stroller get off BART. Nia said, somebody hit me! Latifa looked at her and said your neck! And then Latifa said she got hit but realized she got stabbed. And then he stabbed Nia again in the stomach."
Nia Wilson was declared dead at the scene while Latifa Wilson was rushed to a local hospital. Their sister, 20-year-old Nishiya, was not injured in the attack.
Muhammed told reporters that witnesses had told him the attacker was a white male. The victims were African Americans. "He stabbed my daughter repeatedly," Muhammed said with tears streaming down his cheeks. "This is a parent's worse nightmare."
At a Monday press conference, BART Police Chief Carlos Rojas identified the suspect as a local transient, 27-year-old John Lee Cowell; characterizing him a violent felon currently on parole.
"In my close-to-30-years experience, [it was] probably one of the most vicious attacks I have seen," said Rojas.
After the attack the suspect fled through the parking lot and removed some of his clothes, said Rojas. The murder weapon, a knife, was recovered at an adjacent construction site.
Rojas acknowledged the growing outrage on social media over a possible racial element to the attack but cautioned that investigators have not yet established a motive.
"I know there's been a lot of conversation on social media regarding that, but I don't have one piece of evidence that would suggest this is race-related," said Rojas. "But should that be the case, we will pursue the appropriate hate crimes if they're applicable."
Also at Monday's press conference, a family member urged the community not to jump to conclusions about the motive for the attack.
"We need the community, especially the African American community, to stand down right now," said Nia Wilson's godfather, Daryle Allums. "We don't know if this was racist, we don't know if it was random, we don't know what it was. But we're asking the African American community to stand down right now. Let's get this information and find out what really happened. Let's find out the right facts so they'll be able to deal with the situation ... We need your help. We don't need us to break down right now and act crazy and tear up our city, or do anything that's crazy right now. Our family needs prayer, we need support."
Earlier, family members questioned BART's security at the station, particularly in light of other violent crimes on the BART transit lines and in stations over the last several months.
"My kid was not safe there," said Nia Wilson's mother Alicia Greyson in an exclusive interview with KPIX 5. "You all (BART police) said you were going to have people there and you didn't do it."
"My baby was only 18. She was less than 100 pounds soaking wet. This man just came up and did all this to my baby," she added. "My baby didn't deserve this. She hated BART. She was always saying, 'Mama, I'm scared of BART.'"
Greyson said she found out about her daughter's death from the girl's father and television news reports.
"Her dad called me," she said. "Nobody from Alameda County coroner, the hospital, the BART -- nobody called me," she said. "That's what I had to see on the news. Her dad going crazy (at the BART) and everyone was calling me asking me if it was true."
BART spokesman Jim Allison said the incident took place as a six-car train that started in Richmond and was bound for Warm Springs rolled into the MacArthur station.
"The doors opened," he told KPIX 5. "There was a pair of women who were getting off the train and they were randomly attacked by a suspect who then ran downstairs and fled the station."
Allison said police had train and station video that captured an image of the attacker and were in the process of hunting for the man. Investigators said the suspect was in the same train car as the sisters when it arrived at the station.
BART Police described Cowell as a white male, five-foot-eight, 190 pounds with short, dark hair and a closely-cropped beard and mustache. He is considered dangerous and police urged anyone who sees him to call 911.
Detectives worked gathering evidence and interviewing witnesses all night and the station was finally reopened at 4 a.m. Monday
In a statement, Oakland Mayor Libby Schaaf offered her condolences to the family and promised justice for Nia.
"The senseless and violent stabbing of two young women on a BART train platform last night has shaken our community," the statement read. "Every parent who saw the father of Nia Wilson grieve for his daughter is heartbroken by this horrific act ... OPD has been in constant contact with BART Police, is already providing support on this investigation, and has considerable resources available to further assist in identifying and apprehending the person or people responsible for this attack. "
"At this time, we know of no known motive for this crime," she added. "We all mourn in this moment and we will all work together to bring justice for Nia, her sister and their family."
According to a posting on social media by the Anti Police-Terror Project and Community READY Corps, there will be a vigil for Wilson at the MacArthur BART station at 555 40th St. in Oakland from 5:30 p.m. to 8:30 p.m. Monday.
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