The jury in the trial of a14-year-old girl accused of attempting to murder two teachers and a pupil in a knife attack at an Ammanford school has been dismissed due to a ‘great irregularity’.

A retrial in the case of the teenager will take place next year.

Ysgol Dyffryn Aman was placed in to lockdown on April 24 after the teenager stabbed teachers Fiona Elias and Liz Hopkin, and a fellow pupil, during morning break.

Ms Hopkin was airlifted to University Hospital of Wales in Cardiff after being stabbed in the neck, back, side of her chest, and leg, whilst Mrs Elias and pupil were treated at Morriston Hospital.

The attacker was disarmed and restrained by staff, and was arrested shortly before midday.

She pleaded guilty to having a knife on a school grounds and three offences of wounding with intent, but denied attempting to murder the three victims.

This morning Judge Paul Thomas KC summoned the jury and told them that a ‘great irregularity had compromised their ability to further consider this matter’.

“It is with the greatest possible reluctance that I will have to discharge this jury from returning a verdict,” he said.

He added that the consequences of this were profound.

“Most of all a 14-year-old girl will have to face trial again,” he said. Adding that there was also an impact on court lists and the public purse.

“Unfortunately this jury will have to be discharged. The date for retrial has been established as January 27 next year.”

Judge Thomas sad that he had discussed the reasons why the jury had to be discharged privately with the members.

He thanked the jury for their participation.

“My apologies that matters have gone the way they have,” he said.