A teacher who previously served in the armed forces was sent him back into the classroom two hours after experiencing a traumatic flashback.

Ian Jones today related how his school failed to appreciate his plight as the NASUWT teaching union backed a call for more training on teacher mental health.

In an emotional address to delegates at the union's annual conference in Belfast, the Leicester teacher said he believed his head would want to do everything she could to help him, but did not understand how terrifying flashbacks are.

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He said that he had spent a decade in the armed forces, during which time he was involved in three “very violent events” 30 years ago.

He said that he was diagnosed with life-long PTSD six years ago, which he kept hidden from his employer because he believed that he would be sacked.

“Last year my head sent me for therapy and allowed me the time off, and things got a lot better, and I am able to talk to my wife about what happened,” he said to applause.

“The therapy involves re-living the events time and time and time again, and it means you are going to have more flashbacks, more extreme mood swings, until hopefully you are eventually going to get better.”

Mr Jones outlined how vivid the flashback are, telling the conference:  “Everything comes back: the smells, the feelings of the grass on my face, the emotion of absolute total fear because you believe you are able to lose your life and the people around you are about to lose theirs. You absolutely cannot function."

He said he has had four or five flashbacks this year, which have caused him to have seven days off work, and his head put him on a written formal warning for his attendance.

He added: “Three weeks ago because I was worried about my attendance I turned up to school when I knew I probably shouldn’t and I had a flash back.

“The deputy head found me underneath my desk absolutely terrified, and two hours later the head sent me back in a classroom to teach. I was absolutely humiliated.

“I truly believe my head is not a bad person, and they would do everything they could to help me, but they can’t have any idea of the level of terror that’s involved, or the effect that a flashback has.

“But I truly believe that with training and with understanding of what PTSD does to a person, especially when they are trying to get more soldiers to go back to the classroom, that the head would be able to understand and perhaps not go down the route that she has done, and for everyone the job would be better.”

Delegates passed a motion on teachers' mental health, which includes a call to lobby governments and employers to improve or provide training about mental health issues for teachers and senior leaders.