Homicide detectives say jealousy over a two-timing boyfriend is what prompted Friday's fatal knife attack on an 18-year-old National City woman.
Two other women, also teenagers, are being held without bail as murder suspects.
According to police, the deadly stabbing incident -- in broad daylight -- was planned to the point of buying a standard folding knife.
"They obviously went over there with an intention to confront the victim," said Det. Sgt. Dennis Leach, who headed up the homicide investigation.
"Apparently, there was a dispute over a mutual boyfriend between two of the females."
Investigators say the victim -- identified as Justine Cotton, also known as Justine Brown -- was lured outside of her apartment in the 100 block of East Ninth Street in National City at about 1 p.m. Friday, and died less than an hour later at UCSD Medical Center.
According to Leach, 18-year-old Antoinette Dokes-Hendricks, who had the boyfriend in common, confronted and stabbed Cotton/Brown several times while 19-year-old Rachael Wheelis acted as a lookout and getaway driver.
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A witness managed to get the license number of the Jeep Grand Cherokee that Wheelis was driving, and by 6:45 p.m., the two suspects had been tracked down and detained for questioning.
At the time they gave their statements, they didn't know Justine was dead.
"We have them purchasing the knife before they confronted her," Leach said. "I don't think they quite realized the extent of what they did until after the fact."
Detectives say the man involved in the love triangle was unaware that such a situation might have unfolded.
"There's no rationale behind it," said Leach. "It's just, at this stage, so many lives that were affected and lost and damaged from this point forward."
Dokes-Hendricks and Wheelis are being held at Las Colinas Women's Detention Facility.
Pending the filing of charges by prosecutors next week, they're expected to be arraigned in South Bay Superior Court.
