Scottish classrooms are being "terrorised" by problem pupils because senior staff are reluctant to exclude them, a teaching union has warned.
The Scottish Secondary Teachers' Association (SSTA) welcomed a fall in exclusions - there were 26,844 exclusions from state schools in 2010/11, down 11% on the previous academic year. But the union highlighted that "you shall not exclude" orders remained in some schools, local paper The Courier reported.
But the claims have been refuted by education secretary Mike Russell who said there was "no evidence" behind them.
SSTA general secretary Ann Ballinger said the use of alternative methods of support for "troubled young people" was a positive step, but added there was concern amongst members of the union that some pupils were going unpunished.
"Senior managers in a small number of schools in Scotland are refusing to deal with pupils whose indiscipline is both detrimental to learning and spreading fear and alarm throughout the school community," she said.
"Fortunately these cases are relatively rare but this is of no comfort to pupils and staff terrorised in the workplace.
"Headteachers who refuse to exclude where exclusion is the appropriate action, are simply putting at risk the education of the well-behaved majority of pupils.
''These senior staff rapidly lose the confidence of staff at a time when it is needed more than ever,'' she added. ''Retaining such ill-behaved pupils in school achieves nothing for the pupils themselves, but denies them the opportunity to access the support of expert groups.
But Russell told BBC Radio Scotland: "I accept that some schools don't want to exclude young people because they don't think it's good for them.
"But I think they all know that sometimes, very occasionally, that has to happen.
"I have no evidence that in circumstances where it has to happen, it doesn't happen."