A paedophile teacher with three previous child sex convictions has died while on bail suspected of further offences at a Suffolk school.

Alan Stancliffe, of Pontefract, west Yorkshire, was arrested earlier this year for suspected assaults on three pupils at Kesgrave Hall, which closed in 1993.

The 65-year-old was one of three men to be arrested in the renewed historic child abuse inquiry. He is the second suspect to have died before a charging decision could be made.

Since Stancliffe’s arrest earlier this year it is understood a fourth man has contacted police to make allegations about him. However, at the time of his death Stancliffe had not been arrested in relation to these allegations. He had been due to answer police bail on December 9.

In April this year ex-care worker Kenneth Wheatley was found dead on a railway line near Barnsley two days after being arrested as part of the Kesgrave Hall inquiry. He was also arrested by the National Crime Agency in relation to the investigation into historic child abuse at North Wales children’s homes.

The 62-year-old, who was known as Kenneth Andrew Scott, had previously been jailed for eight years in Leicestershire in 1986 for buggery and gross indecency.

Stancliffe was jailed at Ipswich Crown Court in 2007 after being found guilty of sexually assaulting a pupil at Kesgrave Hall. The former woodwork and technical drawing teacher was imprisoned for two years for three offences between 1978 and 1980.

He had previously been imprisoned for 12 months at Bury Crown Court in June 1999 for subjecting three boys to years of sexual abuse at Kesgrave Hall. Stancliffe had denied seven charges of indecent assault between December 1977 and January 1981, but was found guilty after a trial.

His first conviction for sexual assault was in 1982. However, these did not take place at Kesgrave Hall.

Suffolk Constabulary spokeswoman Charlotte Parker confirmed Stancliffe’s death: “Alan Stancliffe from Pontefract, 65, who was previously convicted of two offences which occurred at Kesgrave Hall School, has died. His death occurred on September 17 in a hospice in Pontefract of natural causes.”

A third suspect is currently on police bail. The suspect, a man from north Norfolk, was arrested on suspicion of indecent assaults at the boarding school ranging from the 1970s to the 1990s.

The renewed inquiry began early last year prompted by a complaint by a former pupil in 2012.

An investigation had taken place at Kesgrave Hall in the early 1990s. In 1992 the Crown Prosecution Service said there was not enough evidence to prosecute any of the alleged abusers following a complaint from a former member of the independent school’s care staff.

Four members of staff who had been suspended, but returned to their posts at the end of the inquiry.