She was placed in a holding cell at the station but was found dead at 6:00am.
Police said a Critical Incident Team from Newcastle would investigate the circumstances surrounding the woman’s death.
In a statement police said: “That investigation will be subject to independent review.”
“All information will be provided to the coroner who will determine the cause of death and make any findings about the events leading to the woman’s death,” the statement said.
“The woman’s family has been notified and our thoughts and condolences go out to the family.
“The welfare of the police officers has been addressed and they are being supported.”