Rihanna was unconscious after Chris Brown attack

Her boyfriend reportedly choked her

Rihanna lost consciousness after an argument with Chris Brown, during which he allegedly choked her, according to reports today.

An argument between the pair escalated to violence as they left Clive Davis’s pre-Grammy party in a silver Lamborghini.

Brown pulled over to the side of the road during the argument, and Rihanna then apparently tossed the keys out the window, according to eonline.com.

Brown got out of the car and when he couldn’t find the keys, she alleges that he threatened to kill her.

He was arrested for alleged criminal threat after turning himself over to police on Sunday (February 8).

–By our New York staff.

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