Teachers at a Glasgow school say they could take strike action over rising incidents of violent pupil behaviour.
Six violent cases have been recorded at Bannerman High School in Baillieston since the Easter break, according to the NASUWT union.
Staff say they are being let down by managers and are considering a walkout if pupil behaviour does not improve.
Glasgow City Council has said any incidents "are dealt with quickly and effectively and a resolution agreed".
However, the NASUWT insists "restorative conversations" which teachers are encouraged to have with disruptive pupils are in some cases having no effect.
'Aggressive and violent pupils'
And they believe too much emphasis is being put on making sure no pupils are excluded from the school.
Mike Corbett, national official for the union, told BBC Radio Scotland's Drivetime programme: "This particular school has had issues for some time with aggressive and violent pupils.
"The teachers don't believe they are getting the proper support from their manager.
"There are examples of the same pupils being disruptive time after time after time and they are still coming back in.
"It's having an impact, not just on our members but on the other kids in the class."
He added: "Perhaps more worrying is examples of either quite serious verbal abuse or sometimes physical violence and vandalism that's been going on for a while in the school.
"There were 20-odd violent incident forms completed last year - even despite lockdown going on - and there were 40-odd before that.
"And yet Bannerman was touted a couple of months back as the only Glasgow secondary school that had not had any exclusions. So there is something not quite right there."
The union, which represents 32 teachers at the school, believes financial pressure to keep violent pupils in mainstream education rather than in a more expensive specialist system is adding to the problem.
Mr Corbett said: "We're not saying that you should be going round excluding pupils.
"But if you've got serious incidents of verbal abuse, violence or vandalism, there are some pupils that need more specialist care and treatment and that doesn't seem to be being addressed by the management at the school.
"Clearly there are some other Glasgow secondary schools who do have violent incidents, with pupils swearing at staff and sometimes resorting to using weapons, and that is being dealt with.
"Exclusion is not necessarily the only answer to that but some schools are using it where it is necessary."
'Valued and respected'
Glasgow City Council said it did not condone abuse "of any sort - either verbal or physical - that is directed towards our teachers or school staff and who deserve to feel respected and safe in their workplace".
A spokeswoman added: "Young people who are not in school are not learning and although exclusions are unavoidable in certain circumstances, our schools work with pupils to find out why they are behaving in such a way and find solutions to support any child in need.
"We will continue to work with unions and their members to make sure everyone feels valued and respected in their working environment and it is not true to say that the school management team are not supporting school staff."