Raynette Turner, 42, died on July 27 inside a Mount Vernon, New York, holding cell, authorities confirmed to BuzzFeed News.
New York State Attorney General Eric Schneiderman on Monday said in a statement that his office's special investigations and prosecutions unit will look into her death.
Executive Order 147 grants the attorney general the authority to assign a prosecutor to look into "the deaths of civilians caused by law enforcement officers."
Turner's autopsy has yet to be completed, and it could take a number of weeks, a spokesperson for the Westchester County District Attorney's office told BuzzFeed News.
On July 25, Turner was arrested for shoplifting from a supermarket, according to local media outlet LoHud. The mother of eight was taken to Mount Vernon police headquarters, and her arraignment was scheduled for Monday afternoon.
Police told LoHud that Sunday evening, Turner said that she was not feeling well. She was transported to a nearby hospital — where she was reportedly treated for high blood pressure — and returned to her holding cell around 10 p.m.
Authorities have said that Turner was the only one in the jail cell at the time.
Police found Turner dead inside the cell on July 27 around 2 p.m. when they came to take her to her arraignment.
Her husband, Herman Turner, spent the afternoon in court waiting for her hearing. He left around 4 p.m., two hours after she had been pronounced dead.
"I want somebody's head to roll on this," he said during a press conference on Tuesday. "I am not going to rest until I get some type of justice for my wife. That's the bottom line."
He added, "No one said anything to me about my wife was downstairs, dead. They just let me sit in the courtroom all day long, waiting for her to come and be seen by the judge."
Turner's attorney, Osvaldo Gonzalez, told LoHud that the Turner family did not receive news of Raynette's death until Tuesday afternoon, when detectives arrived at their residence.
BuzzFeed News has reached out to Gonzalez, and Mount Vernon Mayor Ernie Davis, for further information.
Turner's death comes in the midst of an unfurling investigation into the death of Sandra Bland, a 28-year-old black woman who died in police custody in Texas on July 13.
She is the fifth black woman to die in a police holding in the U.S. cell this month.