THE Stone of Destiny liberators were identified by moles placed in the nationalist movement by the British state, newly released government files have suggested.

The National Archive at Kew files, which have been kept under wraps for almost 75 years, revealed details regarding the hunt to identify Ian Hamilton, Kay Matheson, Gavin Vernon and Alan Stewart.

The four Scottish students reportedly left King George VI “deeply distressed” after liberating the Stone of Scone from Westminster Abbey on Christmas Day in 1950.

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The newly declassified documents reveal that struggling Special Branch detectives used Scottish-based informants to figure out who was behind the heist.

Correspondence from the Metropolitan Police in March 1951 showed that after three months of investigating, they were tipped off that Matheson, then a 22-year-old domestic science student teacher based in Glasgow, was involved.

“On the 24th January, 1951, she was seen at her lodgings in Cleveden Drive, Glasgow, by Detective Inspector Kerr, Special Branch,” the files state.

The National: The Stone of Destiny was used in King Charles's coronationThe Stone of Destiny was used in King Charles's coronation

“She made a complete denial of having anything at all to do with the theft of the stone and said that on Christmas Day she was at home at Firemore, Inverasdale, Ross-shire.”

Matheson’s strong denial and alibi left investigators at a dead end once again.

However, the files also revealed that the Met made a breakthrough after making “certain inquiries” through “certain informants” based north of the border.

According to the files, the information the moles were able to provide brought officers to the “irresistible conclusion that [Matheson] had been one of the party concerned in the theft of the stone”.

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“Information has also now been obtained as to her possible companions,” the document adds.

Officers went to the homes of Vernon, Stewart and Hamilton shortly afterwards.

The trio were students at the University of Glasgow and members of the Scottish Covenant Association, which called for the re-convention of the Scottish Parliament in Edinburgh.

Hamilton (below), who became the final member of the group to pass away in October last year aged 97, was reportedly entirely unperturbed by the prospect of being interrogated.

The National:

“Hamilton denied all knowledge of being concerned in the theft of the coronation stone and flatly refused to make any statement at all,” one senior officer wrote.

“Although he made no complaint to me about being interviewed — in fact he seemed to enjoy the opportunity to explain to me whom he considered the lawful custodian of the stone should be — he strongly resented me having interviewed his friend Miss Matheson.

“All the other persons whom I had cause to see in connection with this inquiry in Scotland were either extremely helpful or politely uncooperative.”

The files also show that the presence of English detectives on Scottish soil did not go down well with senior members of the judiciary.

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John Wheatley, the lord advocate at the time and most senior law officer, raised his concerns with Scotland Yard in the spring of 1951.

He wrote: “The lord justice general [the most senior judge in Scotland] has written to me regarding the recent inquiries by Scotland Yard detectives in Scotland in relation to the theft of the Stone of Destiny,”

“He represented that there was strong feeling that English detectives should come up here to pursue their inquiries and that the method adopted in conducting the actual inquiries was giving rise to a great deal of public dissatisfaction and criticism.

“The lord justice general [Lord Cooper, former unionist MP] expressed the grave concern of the judges and of other people connected with the law regarding the manner in which these interviews have taken place.

The National: The Stone of Scone - the Scottish Stone of Destiny - missing from Westminster Abbey since Christmas Day, 1950 - being removed from Abroath Abbey, Forfarshire, Scotland after being handed to the Custodian of the Abbey James Wiseheart by Scottish

“We must be able to resist any suggestions that undesirable methods are being resorted to.

“If it should transpire that the procedure followed in this case justified critical comment, then steps ought to be taken to ensure that the procedure is rectified in future.”

After a hasty journey from Westminster Abbey to Scotland, where the Stone split in two, and avoiding roadblocks, the gang had authorities on the edge for months.

Eventually, they left the stone, wrapped in a saltire, at Arbroath Abbey in April 1951.

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Sir Hartley Shawcross reportedly persuaded then Labour prime minister Clement Atlee that taking the students to court would backfire.

He argued that they would be regarded as “martyrs if they were convicted, or heroes if they were acquitted”.

Wheatley came to a similar conclusion, writing: “The prevailing view in Scotland is that those who removed the stone were foolish rather than criminal . . . and that it would do no good, and might do considerable harm, to proceed against them.”

The four students admitted their involvement after being assured that no action would be taken against them.