Bradford's system for checking school staff must change following the Soham murder trial, head teachers demanded today.

Although schools chiefs in Bradford said they had confidence in the staff checking system one union branded it a "lottery".

David Hart, general secretary of the National Association of Head Teachers, called for even tighter controls after revelations that allegations of rape, indecent assault and underage sex against double murderer Ian Huntley were not passed on by police when he got a job as a school caretaker.

Mr Hart said the system - where it is up to each force to decide what information is released to the Criminal Records Bureau (CRB) - should end.

He said: "The practice of allowing each individual police force to decide what information beyond a criminal conviction should be disclosed must be brought to an end.

"It is a lottery that throws up totally different sets of information depending entirely upon the discretion of the Chief Constable."

Education Bradford carries out paid-for background checks with the CRB for 75 per cent of Bradford schools before any appointment is made. The other 25 per cent are carried out by other agencies.

As well as police records, the CRB holds records from the Department of Health and the Department for Education and Skills.

When it receives information from the CRB, Education Bradford passes it on to schools before they make any appointment of any member of staff including teachers, classroom assistants and caretakers.

A spokesman for Education Bradford, said: "We are confident in the system we use."

But Mr Hart called for the system to be overhauled.

"This must be dealt with as a matter of extreme urgency because head teachers must not be misled, however inadvertently, into employing people who are a danger to children."

A West Yorkshire Police spokesman said the force followed the national guidelines, which allowed information to be passed on at the discretion of senior officers, but she said it would make changes following any recommendations after the Soham inquiry which was ordered by Home Secretary David Blunkett.

She added: "We will obviously take into account any further recommendations which are made in relation to this matter."

The inquiry was today under way into how Huntley, who was yesterday given two life sentences for the murders of ten year olds Holly Wells and Jessica Chapman, managed to get a job as a school caretaker despite his history of preying on young girls.

Huntley, 29, had previously faced a string of rape and underage sex allegations which did not come to light when he was vetted for the job at Soham Village College.

Newspaper reports claimed today there might be up to 60 victims who have been abused by Huntley, many of them schoolgirls.

Announcing the independent inquiry yesterday, Mr Blunkett said there were "real concerns" about the way police handled intelligence on Huntley's past.

The Chief Constable of Humberside David Westwood, whose force investigated the allegations against Huntley between 1995 and 1999, admitted there were "system failings and elements of human error" and that lessons had been learned.

After Huntley was jailed for life for murdering Holly Wells and Jessica Chapman, the girls' parents described him as "a time bomb".

They told how he imposed "a life sentence" on them when he lured the two best friends into his home on Sunday, August 4, last year and killed them.

Jessica's father, Leslie Chapman said: "Our life sentence started last August. His is only just beginning."

Mr Chapman, 52, said Huntley was "a time bomb just ready to go off and unfortunately both our girls were in the wrong place and at the wrong time".

Huntley's accomplice and former fiancee Maxine Carr was sentenced to three and a half years for conspiring with Huntley to pervert the course of justice, but was cleared of two charges of assisting an offender.

She will serve half that sentence, including the 16 months she has spent at Holloway awaiting trial, and will be freed early next year.

The jurors knew Huntley had once been charged with raping a teenager - a charge that was later dropped.

What they did not know was that he was also accused of indecently assaulting an 11-year-old and having sex with a string of other schoolgirls.

The authorities involved have admitted that the system of checks failed, allowing a man who had come to the attention of Humberside Police on ten occasions to get the job.

In fact, police searching for Holly and Jessica only found out about the rape charge when members of the public rang them.

Holly Wells's father said the families wanted to be involved in the inquiry announced by Mr Blunkett, and said he hoped changes to the law would mean that no other families suffered in the same way.