Two women, aged 39 and 59, are being held on suspicion of perverting the course of justice and suspicion of neglect at the Old Convent, Moor Hall Lane, Bicknacre near Chelmsford, Essex.

They were being questioned by Essex Police, along with two other women, both aged 61, arrested on suspicion of neglect at the same home.

Devon and Cornwall police later arrested a 26-year-old man who is being taken to Colchester for questioning.

More than 100 police officers and social workers were involved in the operation, codenamed Camberley.

It began in May this year as a result of information from journalistic and other sources, said a spokesman for Essex police.

Fourteen adult residents and 12 children, including some with learning and physical difficulties, are now being cared for at a residential home in Colchester.

Detective Chief Superintendent Lee Weavers, who is leading the investigation, said: "Today's operation has been in preparation for six weeks and the focus has been very much on behalf of the children and vulnerable adults.

"Our primary objective is to ensure the safety of the residents and to minimise their anxiety and distress."

He said the premises would be searched for physical and scientific evidence over the next three to five days.

The home has been run by a registered charitable trust called The Family in Trust since it opened in 1985.

Director of Essex Social Services, Mike Leadbetter, said: "This has involved a partnership and close working with police and social services to undertake a very complex operation."

Mr Leadbetter said that the arrests were made following allegations of emotional and physical abuse.