OJ Simpson's slain ex-wife's nephew, Sean Brown, was arrested on Tuesday morning for alleged domestic violence against his live-in girlfriend, Amy Johnson, RadarOnline.com has learned.

According to the booking record, Sean was taken into custody in Orange County, Calif. and is being held on $50,000 bail.

"Police responded to a domestic violence call at about 2:30 a.m. and after an investigation was conducted both parties were taken into custody," Commander Stephen Colon of the Santa Ana Police Department told RadarOnline.com.

"Both parties sustained physical injury but neither required hospitalization."