Police are investigating the death of a 48-year-old woman from Epping.
Officers were contacted by the Ambulance service at around 1pm on June 10 with reports of the sudden death of a woman at an address in Forest Drive in Chelmsford.
She has now been identified as Deborah Nuttall of Woburn House in Woburn Avenue in Epping.
A post-mortem examination has established the cause of death as a heroin overdose. A further forensic post-mortem will be conducted in due course as part of the investigation.
Police are making enquiries to establish the circumstances surrounding her death and ask anyone with information to come forward.
Detective Inspector, Danny Stoten said: “We are currently treating Deborah s death as suspicious and officers are attempting to build a picture of the events leading up to her death.
“I m keen to speak to anyone who saw Deborah on June 10 or anyone who is able to provide us with information on her lifestyle.
A 29-year-old woman from Chelmsford has been arrested in connection with the death and remains in police custody.
Anyone with information is asked to contact Essex Police on 101 or Crimestoppers, anonymously, on 0800 555 111.