Yocairis Diaz ,from NY, was arguing with her brother over a cellphone and then called the police to warn them about killing him.  After she hung up the phone she then proceeded to stab and kill her own brother. She then called again to report what happened as her brother died. Hit the jump for details.
Steph B

A teenager in Queens, New York has been arrested after allegedly stabbing her brother to death in an argument over a cellphone.
Neighbors heard screams from the first-floor Woodhaven apartment after a fight broke out between Yocairis Diaz, 18, and Frank Fortuna, 20, on Friday afternoon.
Diaz called 911 and told the operator: ‘If you don’t get here fast, I’m going to kill this guy!’

Moment later, a neighbor heard another brother Kelvin Diaz, 19, yelling:
‘Help me, help me! He’s dying!’.
‘Frankie was lying on the ground bleeding and his eyes were rolling back in his head,’ the neighbor told The New York Post.

Yocairis called 911 again to report the stabbing, dialed a second number and then fled the crime scene with a neighbor in tow.
She was arrested at noon on Saturday and is currently awaiting arraignment at Queens Criminal Court on a charge of second-degree murder, said District Attorney Richard Brown.

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