A headteacher who attacked his deputy with a wrench at school due to “overwhelming sexual jealousy” has been jailed for more than two years.
Anthony John Felton, 54, armed himself with the tool and sought out his colleague, Richard Pyke, 51, attacking him from behind.
Mr Pyke fell to the ground and attempted to kick away his attacker, before colleagues at St Joseph’s Roman Catholic Comprehensive School in Aberavon, South Wales, heard the disturbance and came to his aid.
CCTV of the incident shown to the court caused people in the public gallery to gasp as Felton landed a blow to the back of Mr Pyke’s head.
Ieuan Rees, for the prosecution, said Felton believed Mr Pyke had slept with another teacher with whom he had recently been in a relationship.
“The evidence of his wife and the admissions he made to her suggested Mr Felton had been in a relationship with another member of staff and had recently discovered he was the father of her child,” he said.
“Furthermore, he believed that Mr Pyke had now begun his own relationship with that lady.”

Judge Paul Thomas KC sentenced Felton at Swansea Crown Court on Friday to two years and four months in jail. Felton was also given a restraining order.
Mr Thomas said an attack by a head on their deputy was “I suspect, entirely without precedent” and was the result of “overwhelming sexual jealousy”.
“That a headmaster of a school should take and use a weapon to try to badly injure their deputy, is I suspect, entirely without precedent,” he said.
“You are more than intelligent enough to realise when you plotted this bizarre attack that the impact and ramifications would be immense and far-reaching.”
The judge said the attack “was in effect an ambush,” with Mr Pyke believing his attacker to be his friend.
While John Hipkin KC, speaking for the defence, said Felton had recently suffered due to the death of his mother and a cancer diagnosis, the judge argued his actions were due to jealousy.
He said: “Ultimately, the trigger for your act of extreme violence was of your own doing, the overwhelming sexual jealousy arising from an adulterous affair and the uncontrollable rage it created in you.”

Following the incident, police said Mr Pyke had been discharged from hospital after suffering minor injuries.
Following Felton’s sentencing, Abul Hussain of the Crown Prosecution Service said: “Anthony Felton struck a defenceless man repeatedly to the head with a metal weapon, demonstrating he had an intent to cause his victim really serious harm.
“The level of unprovoked violence, from a professional in the workplace, was shocking.
“Too often we see attacks of this nature result in life changing injuries or fatal consequences, and thankfully, that was not the result in this case.”