Authorities say Sandra Bland, a 28-year-old black woman from Chicago, hanged herself inside a Texas jail cell this week, but her outraged loved ones say she had no reason to take her life.

Bland was pulled over by Texas Department of Public Safety officers on Friday while on her way to a new job in Texas for allegedly signaling a lane change incorrectly. She wound up on the ground moments later with her hands cuffed behind her back, according to Mashable.

The police say Bland became combative during the stop and was charged with "assault of a public servant," according to the Chicago Tribune. This fact remains unverified, however, since a video shot during the scene only begins after Bland is already face down on the ground, showing that the police slammed her head.

"You just slammed my head into the ground, do you not even care about that?" she asks the officers holding her. "I can't even hear."

One of the officers tells the videographer at the beginning of the video that he "need[s] to leave." Bland thanked the videographer at the end of the video for recording the incident as officers lead her into the back of a police car.

Bland was found dead on Monday in her Waller County jail cell from what authorities say was suicide by hanging.

"I do not have any information that would make me think it was anything other than just a suicide," says Waller County District Attorney Elton Mathis, according to ABC's affiliate in Chicago.

However, Bland's friends and family say that she would never kill herself.

"The Waller County Jail is trying to rule her death a suicide and Sandy would not have taken her own life," longtime friend LaNitra Dean told ABC 7 in Chicago. "Sandy was strong - strong mentally and spiritually."

Following the mysterious nature of her death, an online campaign was started petitioning the U.S. Department of Justice to take over the investigation from the Texas Rangers.

Bland's death comes three months after Freddie Gray, a black Baltimore resident, died while in police custody. The death was later ruled a homicide when a bystander's video of the arrest emerged, leading to the indictment of the six officers involved.