Police in the Dallas suburb of Irving said that Brent, 24, was driving at high speed on a state highway at 2:21 a.m. when his car flipped and then caught fire. The car slammed into an "outside curb, causing the vehicle to flip at least one time before coming to rest in the middle of the service road," police said.
Brown, who had been in the passenger seat, was pronounced dead at a nearby hospital a short time later. Brent suffered "minor scrapes" and was booked into the Irving jail, where he remained on Saturday awaiting arraignment, police said.
"Officers at the scene believed alcohol was a contributing factor in the crash," police said, adding that Brent was given a sobriety test. "Based on the results and the officer's observations and conversations with Price-Brent, he was arrested for driving while intoxicated," Irving police spokesman John Argumaniz said at a news conference.
Brown, 25, was a linebacker on the professional team's practice squad but had not played any games with the Cowboys. He had played in one NFL game for the Indianapolis Colts this season before joining the Cowboys.
Brown also played for the Hamilton Tiger-Cats of the Canadian Football League in 2011 and for two Arena Football League team, the Jacksonville Sharks in 2011 and the San Antonio Talons in 2012. Arena football is played indoors on a smaller field than NFL or Canadian outdoor football.
Brent, 24, has started in five games for the Cowboys and played 12 this season since regular starting defensive lineman Jay Ratliff was sidelined with injuries.
Dallas Cowboys owner Jerry Jones issued a statement expressing his condolences to the family of Brown, who was originally from Missouri.
"We are deeply saddened by the news of this accident and the passing of Jerry Brown. Our hearts and prayers and deepest sympathies are with the members of Jerry's family and all of those who knew him and loved him."
Brent remained in jail on Saturday and his bond will be set at his Sunday morning arraignment, police said. The drunk driving charge was upgraded to intoxication manslaughter, a second degree felony which is punishable in Texas by two to 20 years in prison and a fine up to $10,000.
When police arrived on the scene of the accident after several 911 calls, part of the car was on fire. The 2007 Mercedes sedan was resting on its roof in the middle of the road, and Brent was dragging Brown out of the burning car, said Irving police spokesman John Argumaniz at a news conference.
Police believe, based on gouge marks and other physical evidence at the scene, that Brown was driving faster than the posted 45 miles per hour (72 kph) speed limit.
Argumaniz said the Texas police are still looking for witnesses to the crash, which did not appear to involve any other vehicles.
"There were people on scene," he said. "However, it's our understanding that no one saw what took place. They drove up after the accident."
Brent has been arrested for drunk driving before. While he was on the University of Illinois football team, he was arrested Feb. 23, 2009, on a drunk driving charge, according to Champaign, Illinois, county records. He spent time in the county jail and was suspended from the team, according to local media reports. He eventually left school and was drafted by the Cowboys.
The Cowboys team, which has struggled to live up to high expectations this season with 6 wins and 6 losses, is playing the Cincinnati Bengals in Cincinnati on Sunday.
The tragedy comes as the NFL is still reeling from the death of Kansas City Chiefs starting linebacker Jovan Belcher, who shot his girlfriend to death one week ago before driving to the team's training facility and killing himself in front of the coach and general manager.