PRESS ASSOCIATION -- A woman has been arrested after a care home resident died and two others were taken to hospital.
The three patients were taken to hospital on August 3. One elderly woman died three days later and the other two people remain in a stable condition.
All were residents at the privately-run Partridge Care Centre in Partridge Road, Harlow, Essex.
Reports that they were the victims of insulin overdoses have not been confirmed.
Essex Police have arrested and bailed a 36-year-old woman from Enfield, north London, in connection with the incident.
The Kent and Essex Serious Crime Directorate confirmed it is investigating the "care and treatment of residents" and "historic complaints".
A spokesman said: "Investigators have spoken to family members and residents at the care centre as part of their ongoing inquiries.
"Specialist public protection officers from Essex Police are also working closely with partners in the Essex Safeguarding Adults Board, including the Primary Care Trust, Essex County Council, the Care Quality Commission and Partridge Care Centre, in reviewing all care procedures and ensuring the highest possible standards of care for elderly and vulnerable residents."
Rushcliffe Care Group, which runs the home, has not commented.