Just a lesbian lover's quarrel. The Daily Mail recounts:
NYPD cop Yvonne Wu, 31, was sitting inside her ex-girlfriend, 23-year-old Jenny Li's apartment in Bensonhurst, Brooklyn, on Wednesday at 5pm, when Li returned home with her new girlfriend, Jamie Liang, 24.
Wu - who has been a cop for five years and works out of the 72nd Precinct just four miles away - opened fire, shooting Liang in the chest and Li in the torso. Liang died in the hospital 50 minutes later. Li survived and is still in the hospital but is in a good condition.