Hill End Hospital Adolescent Unit unit abuse allegations reach 74
BBCPolice have spoken to 74 people in relation to an investigation into reports of physical and sexual abuse of child patients at a mental health unit.
The abuse allegedly took place at the Hill End Hospital Adolescent Unit in St Albans between 1969 and 1995.
Hertfordshire Police said it had spoken to "everyone that has made contact" with them since the start of the investigation in November 2017.
The hospital was closed in 1995 and flats are now in its place.
Hill End Hospital, on the outskirts of the town, operated for nearly a century, caring for people with mental health problems.
'Complex investigation'
Police said that 65 people who had contacted the force made allegations about the way they were treated while they were staying at the unit.
Other people who spoke to the police were witnesses to treatment or have made a "third party report", the force said.
Det Ch Insp Jerome Kent said: "This is a complex investigation and we have always expected it to be a long process.
"The team has spoken to everyone that has made contact and full details of their experiences have been recorded."
No arrests have been made in connection with the investigation.