An investigation into allegations of abuse at Medomsley Detention Centre in County Durham is almost complete.
1,361 alleged victims have contacted police to report abuse they suffered at the centre from the 1960s to the1980s.
The victims were all in their teens when they were sent to Medomsley, often for minor offences, until the centre closed in 1988.
Thirty-one potential abusers have been identified and the Crown Prosecution Service is looking into which cases are strong enough to prosecute in court.
The investigation into alleged abuse called 'Operation Seabrook' was launched by Durham Police in August 2013. It is now the biggest investigation of its kind in the country.
It is even bigger than Operation Yewtree, the investigation into sexual abuse allegations, predominantly against television personality Jimmy Savile.
Previous police investigations into the abuse at Medomsley in 2003 and 2005 led to the conviction and jailing of Neville Husband and Leslie Johnson, former members of staff at the centre who have since died.