teaching unions today warned East Lancashire schools were playing a game of "Russian Roulette" when it came to education watchdog inspections.

There was no way of knowing which school might be the next one forced to adopt special measures, they said.

And they have urged education chiefs to produce a short-list of schools causing them concern, in the wake of a second East Lancashire school falling into special measures.

Queen's Park in Blackburn, whose school motto is "To be the best", is the third school in Lancashire, and one of 30 nationally, to be put under special measures after an inspection last autumn.

Today the National Association of Headteachers and the National Union of Teachers said there was no way of knowing which schools could follow Queen's Park and Darwen Moorland High School and come under criticism by the Office for Standards in Education.

Other schools inspected in the autumn term since Ofsted tightened its criteria, include Barden High, Burnley; Gawthorpe High, Padiham; Haslingden High; Whitworth Community High; Primet High and Fisher-More High, Colne; and Beardwood and St Bede's in Blackburn.

While Queen's Park was the worst school in East Lancashire in terms of GCSE grades A* to C passes last year with a rate of 16 per cent, Darwen Moorland fared only marginally better with 22 per cent.

That should send a warning bell to schools which lagged at the bottom of the table - but Accrington's Moorhead High School with a 17 per cent pass rate avoided special measures in its September inspection.

Moorhead headteacher Andrew Bateman, said: "The inspection said we had serious weaknesses which we were aware of. We knew the inspection had changed, which caused us some anxiety, as we were one of the first."

Despite poor performance in league tables sounding some warning bells, Simon Jones of the NUT said there was no way of knowing who would be next.

He urged the borough council to follow standards set by Lancashire County Council, where a confidential short-list of schools causing concern is released to unions.

"It is a game of Russian Roulette as to who will be next under the Ofsted inspections introduced in September and every school is vulnerable," he said.

"I would urge the council to consider preparing for this kind of shock, not necessarily with the public, but at least with other working bodies like the union, so we can liaise with them on matters of teaching problems or budget issues."

Lancashire County education portfolio holder Alan Whittaker said: "We endeavour to keep as many people as possible in the know, in vague and confidential terms, about performance or problems in terms of teaching shortages or standards. Then we are as best prepared as possible."

Queen's Park High School and Moorland High have both been told they have two years to turn around the "unsatisfactory" education they provide. The rate of schools being put into special measures in the autumn term, compared with the year before, almost doubled as a result of the change in inspection criteria.

David Fann, council member for Lancashire's NAHT, said: "The inspector for schools said the 'bar has been raised'. It is not just schools with poor results -- it could be anyone.

"There is a lot of stigma attached to being in special measures but very little to know who will be affected."