The start of the autumn term has been delayed for hundreds of pupils because vetting checks on new staff have not been completed.

The latest figures from the Home office put the number of outstanding urgent checks at about 12,000 - though it is confident of doing them by next week.

Too late for ADT City Technology College in Wandsworth, south-west London, which reopened on Wednesday, and had to tell about 500 pupils to stay at home until next Tuesday.

We've been let down by the agency, because they haven't produced the goods

Chris Hassell, head teacher

There are checks still to be run on 12 new teachers - and until these have been completed, the school is not opening to all pupils.

Those in GCSE and A-level exam years have begun the term as planned.

Hunreds of checks are also incomplete for staff in Leicestershire, which traditionally begins the term earlier than most counties.

Leicestershire County Council said it was not aware of any schools having to close, but said checks on 279 staff had still to be completed.

'Sad situation'

A spokeswoman for Leicester City Council said it knew of two schools - Moat Community College and Kestrels' Field - being forced to make timetable cuts.

Head teacher at Kestrels' Field, David Axton, said 85 out of a total of 350 pupils were asked to return home when they arrived with their parents on Thursday morning.

The Criminal Records Bureau was meant to be a speedy one-stop shop

Mr Axton said he was hopeful the situation would return to normal next week.

A newly-qualified teacher at the school, Celia Brierley, said she had sent off her application form four weeks ago - and had been told she would be allowed to teach provided she wasn't alone in the classroom.

She was told only 10 minutes before she was due to start her first day's teaching on Thursday that she would not be allowed near the children.

"It's a big disappointment not only for me but also for the children as well, because they were looking forward to meeting their new teacher and having to go home quite upset some of them," she said.

Huge backlog

The head teacher of Taylor Road Primary School in Leicestershire, Chris Hassell, said the Criminal Records Bureau (CRB) - supposed to be a new one-stop shop for speedy checks on teachers - had let everybody down.

"I do think we've been let down by the agency, because they haven't produced the goods.

Head Chris Hassell: "Let down" by the agency

"They haven't ensured that people who work with children are checked in sufficient time for them to be employed at school by the start of term."

The Department for Education backed ADT College's decision to keep pupils away, saying that "child protection is paramount and non-negotiable".

Extra priority

The Home Office said later that it was working with the CRB and the DfES to clear the backlog by 4 September, when most schools start back.

It said the CRB would try to make sure "all but a handful" of checks were processed in time.

Of 22,000 or so applications identified as being priority ones last week, 9,932 had now been issued.

Of the others, 6,945 were being given extra priority.

But 5,478 required more information for various reasons and would take longer to process.

Closure fears

The CRB covers England and Wales - where the leader of Rhondda Cynon Taff County Borough Council, Pauline Jarman, said: "The significant numbers that remain unchecked within our authority are causing concern.

"It leaves headmasters, school governors and local education authorities in a difficult position.

"An additional worry is that if this situation is not resolved, nurseries and schools may be forced to compromise their own quality standards by employing staff who are not cleared.

"It could even mean that day nurseries and schools are facing closure, because the staff they need have not been cleared to start work."

Emergency measures

An extra 100 staff were taken on at the CRB who worked through the bank holiday weekend to try to clear the backlog.

By Tuesday, 4,000 of the most pressing 25,000 applications had been completed.

Teachers and other adults who work in schools have to undergo a double clearance before they can work with or near children.

Their names must be checked against the government's confidential databases of people deemed unsuitable to work with children.

They must also have checks on police records, a process that can take more time as staff may have worked in several different police force areas.

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