The FBI is investigating the death of a black woman in police custody after she was pulled over for failing to use her turn signal

On July 10, a Texas department of safety officer pulled over Sandra Bland, a black woman, for allegedly failing to signal a lane change. By Monday, she was dead in a jail cell in an apparent suicide. 

Now, the FBI is investigating her death, USA Today and other outlets reported. 

Bland ended up in police custody after a routine traffic stop during which she was arrested for assault on a public servant after she became "argumentative and uncooperative," according to a DPS statement. 

An alleged video of the end of the arrest, shown below, appears to show officers cuffing Bland while she lays on the ground yelling that they slammed her head into the ground.

One of the officers then tells the bystander filming, "You need to leave."

The full story, however, remains unclear.

"I couldn't tell if he slammed her down there or it was a maneuver she did trying to stop him from putting her in the car caused her to be put on the ground," one woman, who had a clear view of the incident from a barber shop across the street, told USA Today.Regardless, the department of public safety claims EMS was called to the scene - and that Bland refused a medical review.In the morning a few days later, a Texas Ranger found Bland in her cell "not breathing from what appears to be self-inflicted asphyxiation," the Waller County Sheriff's Office said in a statement, according to The Houston Chronicle. Officials later said Bland used a trash bag, an item normally found in cells, to hang herself.She had been given breakfast just two hours earlier, according to The Chronicle.In the throes of a heated national discussion about police brutality and race, Bland's family is questioning the cause, and motivations, of her death. "Based on the Sandy that I knew, [suicide] is unfathomable to me," Bland's sister said at a press conference in Chicago on Thursday, according to The Guardian. Another friend says he had spoken to Bland the day of her arrest and she seemed in "good spirits.""She was looking forward to posting bond Saturday and getting out. So you don't go from that to hanging yourself," he told USA Today.The same friend also says Bland told her the officer who pulled her over "snatched her out of the window and slammed her on her face on the ground." Bland's death is currently under investigation by the Texas Rangers, and the investigation recently expanded to include the FBI. Additionally, DPS is conducting an internal review of the traffic stop. 

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