Police investigate alleged threats towards Cardiff staff by Willie McKay

The man who brokered the deal that brought Emiliano Sala to Cardiff City two days before his death in a plane crash is under investigation after reportedly threatening to 'burn' the Premier League club and warning 'I'll shoot the lot of you'.

Willie McKay, who is no longer registered as a football agent but helped his son Mark complete the ill-fated Sala transfer, has been the subject of an investigation by South Wales Police over claims he threatened to kill Cardiff staff in a dispute about who is liable for damages following the tragedy.

It comes three weeks after McKay is said to have threatened to 'kill everybody' at the club after being embroiled in the complexities that came following the tragic incident.

In new developments, The Telegraph claim that McKay also 'found out where one of the persons to whom threats were allegedly made lived' before going on to confront him at a nearby cafe.

He also claimed 'I'll burn Cardiff' during a furious rant while on the phone with a member of Cardiff's staff and the alleged victim McKay confronted in person later received threatening calls in which he said, 'I'll shoot the lot of you', and, 'You don't know who you're dealing with'.

The Welsh force have said the investigation 'has been transferred to the Metropolitan Police Service'.

It is understood at least one of the alleged threats has been claimed to have occurred in London and that was confirmed in a statement from the Met Police on Thursday.

'(We) have received an allegation of a possible public order offence that took place at Kendall Street, W2 on Friday, 22 February,' a spokesperson told Press Association Sport.

'Officers from Central Area Command Unit are investigating. No arrests have been made at this time.'

Sala died, along with pilot David Ibbotson, when the Piper Malibu aircraft they were travelling in came down in the English Channel on January 21.

That prompted an outpouring of grief throughout football but particularly at the 28-year-old striker's former club Nantes and Cardiff, the team that had just made him their record signing.

The united response did not last long, though, as Nantes pressed for payment of their £15million fee, while Cardiff said they wanted to wait for a full investigation into the accident.

Within days of Sala's death, the focus had shifted to how the deal was put together and specifically what role McKay, 59, played in the transfer and who arranged the doomed flight.

The Monaco-based Scot has explained that he was helping his son Mark, who was acting for Nantes, to complete the deal and that he paid for the flight, and several others related to the transfer, but did not choose the pilot or the plane.

That, he claims, he left to his usual pilot Dave Henderson, who was unavailable on the day in question.

It has also emerged that his son Jack McKay, who is on Cardiff's books with his twin brother Paul, made some of the arrangements for the flight with Sala.

With Cardiff understood to be concerned that their insurance may not cover the costs of the transfer if laws were broken in relation to how the flight was paid for or whether Ibbotson was qualified to fly it, relations with the McKays have deteriorated badly.

Willie and Mark McKay have repeatedly denied any wrongdoing and Willie McKay has accused the club of 'trying to throw him under the bus'. He also told the BBC that he and his family have 'been through hell'.