Hundreds of mourners gathered Saturday for the funeral of Sandra Bland, a black woman found hanging in her cell three days after her arrest for a minor traffic violation, calling for justice.

The 28-year-old black woman was stopped by a white Texas trooper for failing to signal a lane change on July 10. The released dash-cam video showed that after Bland refused to step out of her car, the encounter escalated into a physical confrontation, with the officer attempting to drag her out and threatening to "light her up" with his gun.

On a charge of assaulting a public servant, Bland was put into a Texas jail, where she was found hanging with a plastic trash bag around her neck on July 13.

An autopsy ruled out the possibility of homicide, yet the questions of how and why of Bland's death remain perplexing.

The grief-stricken mourners attending the funeral at the DuPage African Methodist Episcopal Church expressed their sorrow mixed with fury.

"This is not a moment of defeat. This is an hour of victory ... We are not funeralizing a martyr or a victim. We are celebrating a hero," said Reverend James Miller, who led the funeral service.

In their speeches at the funeral, Illinois politicians U.S. Senator Dick Durbin and U.S. Representative Bill Foster called for a full federal investigation into Bland's tragic death.

This incident is the latest that triggered an outcry over racial discrimination in the U.S. law enforcement system.

The day after Bland committed suicide, Kindra Darnell Chapman, an 18-year-old black girl, hanged herself with a bed sheet in a jail cell in Homewood, Alabama.

The tragedy occurred roughly an hour and a half after she was booked into jail on charge of first-degree robbery for allegedly stealing a cellphone. The reported description of the event has aroused skepticism.

In less than a week after Bland's death, a white police officer shot and killed an unarmed black man, 43-year-old Samuel Dubose, on July 19 after a roadside altercation in Cincinnati.

Spencer Lee McCain, an unarmed 41-year-old black man, died on June 23 after being shot by three police officers at his home in Maryland, while a woman who said he had threatened to beat her was there with her two young children.

Thousands took to the streets on Feb. 24 when the Justice Department announced that George Zimmerman, the officer responsible for the death of Trayvon Martin, an unarmed 17-year-old black student, was exempted from prosecution for lack of evidence.

The Ferguson unrest, a series of protests sparked by the fatal shooting of an 18-year-old black man, Michael Brown, by a white police officer on Aug. 9, 2014, in Ferguson, Missouri, lasted more than half a year, with intense conflicts between angry citizens and police officers.