Irving police spokesman John Argumaniz said the accident happened about 2:20 a.m. Saturday in the Dallas suburb. Argumaniz says Brent was speeding when the vehicle hit a curb and flipped at least once.
Argumaniz says Brown was found unresponsive at the scene and pronounced dead at a hospital.
The police spokesman says officers conducted a field sobriety test on Brent and arrested him. The charge was upgraded after Brown was pronounced dead.
The Cowboys didn't immediately respond to an email request for comment.
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