More than 80% of teachers have suffered work-related stress over the past two years, a survey found today.

And the overwhelming majority have been bullied or harassed by pupils or their colleagues in the staffroom, the NASUWT union said.

Chris Keates, the union’s general secretary, said the survey of 5,000 teachers made "disturbing reading".

"Too many teachers are working in intolerable circumstances," she said at the union’s annual conference in Belfast.

"It is unacceptable that 81% of those surveyed have suffered from work-related stress in the last two years. An overwhelming majority of teachers have been subject to some form of bullying and harassment in the same period. It is clear that the health and welfare of staff is not being safeguarded."

The findings followed warnings that teachers’ careers are being ruined by pupils who falsely claim they have been abused or post humiliating pictures of their teachers on the internet.