DETROIT (WWJ/AP) – A preliminary exam began Friday in the most recent assault case against former Cass Tech football star Jayru Campbell who is accused of pushing and choking his girlfriend during an argument over a cell phone.

Aside from the assault charges, Campbell —  recently served time for body-slamming a school security guard — is also facing a probation violation.

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A 17-year–old girl identifying as Campbell’s ex-girlfriend, who appeared in security camera footage which was shown during testimony, claimed that she and Campbell got in a dispute over something on her cell phone which things escalated.

As is seen on the security tape, after the two discussed something in a classroom, a confrontation took place in a hallway staircase at the school. The tape allegedly shows Campbell, also 17, grabbing the girl’s cell phone, pushing her and then grabbing her around her neck; at one point picking her up off the ground with his hands around her waist.

 (credit: Mike Campbell/WWJ)

(credit: Mike Campbell/WWJ)

It reportedly took a group of Campbell’s fellow football players to pull him off of the alleged victim.

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Campbell’s defense attorney argued that it appeared the girl was actually the aggressor in the situation and that he was just trying to look at her cell phone.

During testimony, the alleged victim’s mother talked about some red marks she noticed around her daughter’s neck following the incident.

Jayru Campbell's ex girlfriend testifies. Reports were asked not to photograph her face. (credit: Mike Campbell/WWJ)

Jayru Campbell’s ex girlfriend testifies. Reports were asked not to photograph her face. (credit: Mike Campbell/WWJ)

Campbell had been released from jail just a few hours prior to the alleged assault  after serving time for body-slamming a security officer in a hallway at Cass Technical High School, where he was the star quarterback

Campbell was sentenced in May to 60 days in jail after he admitted he slammed the officer head-first on Jan. 22.

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