A couple has been left devastated after their beloved puppy was mistakenly given a lethal injection by a vet.

Molly the ten-week-old border collie was being monitored after she became unwell following the injection of her second routine puppy vaccination.

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But she was then accidentally given a solution of Potassium chloride in place of heparinized saline - killing the young pup.

And her owners, Wayne and Lisa Maguire, claim they have been asked to PAY for the care Molly received at WJ Downes, in Aberystwyth, before the fatal error.

Mr Maguire, from Lledrod, in Ceredigion, Wales said: "She had her second vaccination jab on the Monday. She reacted to that and it gave her a temperature and diarrhoea.

Glasgow Times:

"She initially recovered, but went downhill again and she went back in and was put on a drip.

"My wife called the vets on the day of the incident and she was told they wanted to keep her in to care for her.

"The vet called back a few hours later and said Molly had died.

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"She was a healthy pup. We are frustrated, annoyed and upset about it. We wouldn't want anyone to go through what we went through."

A letter from the practice's insurers, The Veterinary Defence Society Limited, confirms Molly's death was caused by "an inadvertent injection with a solution of Potassium chloride in place of heparinized saline".

Mr Maguire said the surgery admitted Molly's death was caused by the incorrect storage of medication and has apologised.

A personal letter from the vet who administered the injection, Sharon King, sent to the couple on 30 September, reads: "I wish to extend my heartfelt apologies to you both for the untimely death of Molly.

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"I realise my apology cannot ease your grief, but I would like you to know that I am truly devastated by the whole event, and that the consequences of my well intentioned actions on 4 August resulted in Molly's death.

"I hope you can accept both my apologies and sincere condolences for your loss."

Despite the couple requesting £530 in compensation, VDS offered Mr and Mrs Maguire just £300 "in a pragmatic attempt to draw this sad incident to a close".

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After rejecting VDS' offer, the couple were sent another letter on 26 October, which read: "Your allegation that our members have shown you 'utter contempt' in their handling of this tragic incident is both refuted and resented.

"Although we have no proposal to increase it without the requested documentation, our offer remains open."

Mr Maguire added: "It is not about the money for us, it is about the way they have treated us - there is no personal nature to it. All the way through, it has been us chasing them.

"We have two other collies who are about four years old. One is quite nervous and we were worried he wouldn't take to Molly.

"What actually happened was he played with her and they became close, and to lose a pup after that was a bit of a shock to the system."

A statement from WJ Downes read: "There is an ongoing investigation into the issue and we are thus currently unable to comment."