DETECTIVES are investigating abuse claims by more than 60 former pupils of a Suffolk school in what is now believed to be the county’s largest inquiry of its kind.

Ex-students of Oakwood School in Stowmarket, which closed in 2000, have made various physical and sexual claims relating to their time at the school.

A total of 75 men are currently part of a civil claim relating to emotional, physical and sexual mistreatment they say they suffered while at the Suffolk County Council-owned establishment.

This week solicitors acting on behalf of the ex-students served court proceedings on the council, which has 28 days to file a defence or admit liability.

Meanwhile, Suffolk police said they have now received 63 complaints alleging abuse. It is understood these are against at least five people linked to the school between the 1970s and 1990s.

Many of those who have come forward say they are still traumatised by what they say happened to them.

No arrests have been made so far, but the police inquiry has being continuing for many months, and has been prolonged by further alleged victims coming forward.

Seventeen more former students have contacted police since January, when the inquiry involved 46 ex-pupils.

Lucy Sheehan, a spokeswoman for Suffolk Constabulary, said: “This is one of the largest investigations of this type that we have been involved with.”

The civil case is being handled by Cambridge-based solicitors Andrew Grove and Co.

Mr Grove said: “The county council must confront these serious allegations of an institutionalised violent regime at Oakwood, where we say harm became the norm.”

A spokesman for the county council said it urged anyone with information to come forward, but it could not comment further while a police investigation was taking place, with which it was co-operating fully.

Oakwood opened in 1974 as a school for pupils with emotional and behavioural difficulties. It closed temporarily in December 1999 after serious concerns were expressed. Although it was re-opened, it closed for good the following year.

The only other comparable criminal case in terms of multiple alleged victims is that of Derek Slade, the sadistic paedophile headmaster at St George’s School which was based in Great Finborough, near Stowmarket, and near Wymondham in Norfolk.

Slade, 63, was jailed for a total of 21 years at Ipswich Crown Court in September 2010 after being convicted of more than 50 offences, including a catalogue of sexual and physical abuse on 12 pupils between 1978 and 1983.

Further alleged victims are understood to have come forward after his conviction, however no other prosecutions were brought against Slade.

Currently more than 30 ex-pupils of St George’s are pursuing civil claims through three different specialist legal firms.