The death of an Illinois woman found hanged in her Texas jail cell in what local authorities said was a suicide will be investigated as thoroughly as a murder, the local district attorney said on Monday.
Sandra Bland, 28, was found dead on July 13, three days after she was arrested for assaulting an officer during a traffic stop in Waller County, about 50 miles (80 km) west of Houston, authorities have said.
The Waller County Sheriff's Office said Bland took her own life and the death was ruled a suicide by the Harris County Medical Examiner's Office. But her family and friends have publicly questioned the official account.
At a news conference on Monday, Waller County District Attorney Elton Mathis said there were "too many questions" to determine how she died.
"This is being treated like a murder investigation," Mathis said. He added that officials would examine fingerprints and run DNA tests on the plastic trash bag used in her hanging.
Bland's family has called for an independent autopsy and for the U.S. Justice Department to open an investigation, saying the young woman had moved to Texas from Chicago to start a new job and would not have taken her own life.
They also told Chicago local media that Bland, a black woman, was outspoken about allegations of bias and excessive force by U.S. law enforcement in a year that saw protests across the country following the killings of unarmed black men by white officers in New York, Missouri and South Carolina.
Last week, the FBI and Texas Rangers, a statewide police and investigation agency, said they were looking into Bland's case.
The trooper who took Bland into custody following a traffic stop in Prairie View, Texas, has been put on desk duty for violating protocol during her July 10 arrest, the Department of Public Safety said.
Bland was accused of becoming combative and assaulting the officer, according to arrest records and local media.
The Waller County Sheriff's Office on Monday released three hours of footage from the jail on the morning of her death, the Houston Chronicle reported. A female officer who apparently saw Bland hanging in her cell is seen in the footage running for help, the newspaper said.
Several officers administered CPR to try and revive her, the newspaper said, citing the sheriff's account.
(Reporting by Victoria Cavaliere; Editing by Catherine Evans)
Correction: An earlier version of this story included a headline that said the investigation would be treated "as" a murder investigation. It has since been updated.