Man killed his mistress’ ex

A CHEATING killer murdered his mistress’ ex after he found out about an affair.

John McKay, 46, knifed William Scott to death at the victim’s flat in Airdrie, last April.

He had earlier been having secret sex trysts with Louisa Corcoran, 34 – the mum to five of William’s children.

But, the pair were caught when McKay’s girlfriend Marion Carson discovered he had set up a fake Facebook page to chat with Louisa online.

Marion revealed the fling to a fuming William, 43 – before he called Louisa to hurl abuse at her.

When McKay then learned what happened to Louisa – his “number one” – he stormed to William’s flat and stabbed him seven times.

A jury heard it was a young girl who made the grim discovery of his dying body in the bloodstained property.

The drama emerged as McKay was convicted of murder following a trial at the High Court in Glasgow.

The first offender – who denied the accusation – faces life in jail when he is sentenced next month.

The court heard how McKay started an affair with Louisa in early 2016. His mother was a neighbour of Louisa and McKay would sometimes repair her car.

She agreed McKay was “just a nice man”. They were initially friends before getting closer.

Louisa had been in a 15-year relationship with William Scott – but insisted they had separated by the time she started seeing McKay.

McKay had told her he had been in a 19-year relationship, but claimed he had split with Marion after they apparently “fell out”

He called Louisa his “number one” and that he “loved” her.

The court heard, however, Louisa suddenly ended the fling in early April – just weeks before the murder.

She sent message claiming her “head was all over the place”.

McKay was remanded in custody pending sentencing on April 19 in Edinburgh.