Police in Essex say they will "explore in scrupulous detail" claims that children in care in the 1980s and 1990s were sexually abused.
The allegations emerged at a meeting between Chief Constable Stephen Kavanagh, the county's Police and Crime Commissioner, and people involved in child protection work at the time.
During the 1980s and 1990s, a number of investigations were carried out and two convictions were secured.
However retired district psychologist Robin Jamieson, Jenny Grinsted, a former Clinician Manager for the Suffolk Child Sexual Abuse Treatment Service in Essex, as well as a youth worker and probation officer Rob West, believe the inquiries were not thorough enough.
They raised serious concerns about alleged historical sexual offences against children, particularly boys in local authority or foster care, and the safeguarding and support provided for a large number of young people in Essex who may have been victims of serious abuse.
Essex Police are appealing for anyone with information about abuse during this period, or victims of sexual abuse as a child at the time, to contact them.
Essex Police says its first step will involve reviewing any evidence and what was known about abuse at the time which could inform any future investigation.