Senior Kinahan gang figures Liam Byrne and Thomas Kavanagh jailed in the UK

He had hoped that by leading the UK's National Crime Agency (NCA) to a buried stash of 11 “fearsome” weapons, he could influence sentencing in a multimillion-pound drug smuggling case.

Running the conspiracy from prison, Kavanagh enlisted the help of his brother-in-law, 44-year-old Liam Byrne, and associate Shaun Kent, 38, in the plan to deceive the NCA.

Byrne – who fled to Majorca after the events – was jailed for five years while Kent was handed a six-year prison sentence after a two-day sentencing at the Old Bailey in the UK, with all three defendants appearing via video link from HMP Belmarsh on Tuesday.

Kavanagh will serve his sentence consecutive to his jail time for previous offending.

But Kent has already served more days on remand than the sentence imposed on Tuesday, and therefore is expected to be released from prison.

The trio admitted the conspiracy last month ahead of their trial at the same court and Judge Philip Katz KC said during sentencing: “I propose to deal with this case as one overarching criminal plan.

“It was all designed to help Thomas Kavanagh with his sentence.

“The means chosen to achieve the purpose was to put together a cache of firearms to fool the NCA… and in due course to fool the judge.” The judge called the weapons “fearsome”.

Speaking to Kavanagh, Judge Katz added: “You Thomas Kavanagh were at the heart of these conspiracies which were designed for your benefit. You were in prison and still able to pull the strings.” In May 2021, Kavanagh provided information to the NCA which led them to a field in Newry, Northern Ireland, where two holdalls were unearthed.

They contained seven machine guns, three automatic hand guns, an assault rifle and ammunition.

The plot was foiled after the NCA uncovered incriminating messages on encrypted EncroChat which had been cracked by French counterparts.

Between January 2020 and June 2021, the defendants agreed to “acquire as many arms as possible” from the UK, Netherlands, the Republic of Ireland and Northern Ireland.

Kavanagh had run the conspiracy from HMP Dovegate where he was serving a three-year sentence for possession of a stun gun and had been remanded on serious drug charges since March 2020.

Those charges related to smuggling “multiple kilos” of cocaine and cannabis into the UK for which he was sentenced in March 2022 to 21 years’ prison.

Prosecutor Tom Forster KC said on the first day of sentencing: “Put shortly, Thomas Kavanagh’s plan, with which the other defendants agreed and put into practice, was to assemble as many weapons and ammunition as possible, acquiring the arms from various criminals, then conceal them and finally reveal their whereabouts to the NCA.

“In this way, the conspirators intended to fool the authorities into concluding the assistance was genuine, when it was not, so that Thomas Kavanagh would be rewarded for helping the authorities to recover dangerous weapons by way of a considerable discount from his sentence.

“However, the true position was that he and his co-conspirators did not intend to provide any real assistance because they had orchestrated the acquisition of weapons and ammunition through their own serious criminality. It was a ‘put up job’.” Mr Forster said the plot was laid bare over in encrypted messages on EncroChat, described as “WhatsApp for criminals”.

According to the NCA, messages included Kent telling Byrne that Kavanagh had asked him to pass on a message to “keep on about locating them things (firearms) for him mate”, adding “he said try get as many of them as you can… only chance he’s got on getting good result out of this case mate”.

Kent also received a message saying Kavanagh was “under massive pressure and time’s against him” to get the firearms in position before he was due to appear in court again.

Kent was said to have performed several roles, including “messenger boy” by receiving instructions from Kavanagh via a middleman in prison.

He then used his EncroChat device to relay instructions to others tasked with him to obtain the guns and ammunition, the court was told.

Byrne was a close criminal associate of Kavanagh as well as his brother-in-law and they lived near to each other in Tamworth, Staffordshire.

He acted on Kavanagh’s direction to acquire firearms and ammunition and added “much-needed impetus” to progressing the plot.

Kavanagh, Byrne, from Dublin, and Kent, from Liverpool, admitted last month ahead of their trial at the same court two charges of conspiring to possess a prohibited weapon, and two charges of conspiring to possess prohibited ammunition, between January 9 2020 and June 3 2021.

Kavanagh and Kent also admitted conspiring with others to pervert the course of justice.

NCA Branch Commander Ty Surgeon said: “At the instruction of their leader Thomas Kavanagh, Shaun Kent and Liam Byrne orchestrated a cynical and dangerous plot to plant a cache of weapons so Kavanagh could direct the NCA to them and reduce his time in prison.

“These weapons were viable and deadly weapons that were in the hands of a criminal gang, loaded and ready for use in criminality. What this group didn’t know is their EncroChat messages had been unveiled for law enforcement to see, showing every detail of their plan.”