(; ; MAC) was a paramilitary Welsh nationalist organisation, which was responsible for a number of bombing incidents between 1963 and 1969. The group's activities primarily targeted infrastructure transporting water to the English cities of Birmingham and Liverpool, in addition to the investiture of Prince Charles as Prince of Wales.
History
MAC 1
Tryweryn The first iteration of MAC was established in 1962 at Owain Williams' café in Pwllheli, Gwynedd. After two years of working as a cattle rancher in Canada, Williams returned to his family farm near Nefyn on the Llŷn Peninsula in 1959. On his return, he had become radicalised by Plaid Cymru's failure to prevent the flooding of Tryweryn, which was being planned by Liverpool Corporation with the intention of constructing a reservoir supplying water to the city. Williams' father helped him to purchase a mortgage on the Espresso Bar and Grill in Pwllheli, which quickly became a meeting spot for Welsh nationalists. It was from the café that Williams would first recruit Robert Williams, from Criccieth, and Edwin Pritchard, from Nefyn. On 15 October 1962, the three young men raided a granite quarry near Llithfaen to steal explosives from the site. However, the trio discovered upon their return to the café that they had only succeeded in acquiring hundreds of detonators, which they promptly hid across the local area. Following the raid on the quarry, Williams determined that his two accomplices were not suitable for his plans and would crack under police interrogation. He subsequently recruited two new accomplices: John Albert Jones, a former officer in the Royal Air Force Police from Wrexham, and Emyr Llywelyn Jones, a well-connected student at University College Wales. Together, the three planned to attack the Tryweryn construction site with explosives. Williams and John Albert Jones initially planned an ambitious strike at ten locations across the site; however, Emyr Llywelyn preferred a more symbolic protest, akin to the protest at Penyberth in 1936. The trio agreed on Emyr Llywelyn's suggestion and began reconnoitring the construction site throughout the harsh winter of January 1963. It was decided that they would attempt to destroy the transformer powering the site on the evening of 9 February 1963. Upon agreeing on their plans, the three men swore the oath of Mudiad Amddiffyn Cymru, which read:I promise to keep the activities of the movement and the names of the members secret; I promise neither to kill nor to injure any man who as part of his duty attempts to prevent me and I will do everything in my power to ensure that no one is injured or killed as a result of any act on my part. I promise not to undertake any positive act without consulting the other members of the movement.
Leading up to the day of the attack, accomplices of the group in Pembrokeshire had stolen gelignite from a colliery, supplying the necessary explosive material. Similarly, Dai Pritchard, a draughtsman from New Tredegar, had acquired a Venner time switch to use as a timer. Pritchard had been fined for attempting to damage the same transformer the year prior and possessed both the necessary technical knowledge and, in addition, links with the Irish Republican Army (IRA). With the gelignite and timer in his possession, Pritchard travelled north to supply the three saboteurs with the assembled explosive device and provided a demonstration with a small blast on a beach near Pwllheli. On the night of the operation, Wales was gripped by the coldest winter since 1740. The saboteurs pressed on with their plan regardless, even despite Owain Williams' wife, Irene, being rushed to hospital in Bangor with pregnancy complications shortly beforehand. The trio met at their planned rendezvous point in Pwllheli, from where Emyr Llywelyn drove them in a rented red Vauxhall Victor towards the target. Most of the roads in the area surrounding the dam construction site were closed due to snow and ice, with only the A494 between Bala and Dolgellau remaining open.
Shortly after passing Dolgellau, a rear tyre popped, causing the sabouteurs' car to skid across the road. Fearing being spotted, the men pushed the car off-road so they could replace the tyre; however, they discovered that they had no jack, requiring two of them to lift the car with their hands. Having replaced the tyre, the group continued on to Cwmtirmynach, from where they hiked across a section of the snow-covered Arenig mountains using a sheep track. As they approached the transformer, the saboteurs were forced to drop to the ground and crawl through the snow for hundreds of yards, leaving a trail behind them. The three narrowly succeeded in avoiding the six guards present at the site and planted the bomb beneath the transformer, which was set to detonate at 3:15 a.m. After rigging the bomb to explode, the group fled back into the mountains and escaped to the rented car in Cwmtirmynach. However, Emyr had badly injured his leg on barbed wire while clambering over a wall and was bleeding, preventing him from driving. Attempting to stem the bleeding from his leg wound, Emyr used his handkerchief embroidered with the initial 'E' to apply pressure, but he later dropped it near the scene during the group's escape.
With Emyr Llywelyn unable to drive, Williams took the responsibility. The icy conditions proved too severe for Williams, who skidded the car into a snowdrift on the road approaching Cerrigydrudion while attempting to pass a van that had done the same. The trio panicked as the driver of the van approached their car, and Williams attempted to pass himself off as an Englishman by asking, in a feigned English accent, "I say, old boy, do you know if this road goes anywhere?" The young van driver, Hugh Roberts from Cwmtirmynach, was suspicious of the "Englishmen" and replied, "No, it's closed; I'm stuck, too, you see." In Williams' autobiography, he recounted how he had told his two accomplices to let him do the talking before referring to them both as Charles and Steve while instructing them to help push the van in the presence of the driver. After pushing both the van and the Vauxhall out of the snow, the trio hastily drove off back in the direction of Bala, as Williams had boxed himself into a corner with his English persona. Intent on maintaining the masquerade as he departed, Williams shouted from the window of the car, "Blast these Welsh roads; I'll be glad to get back over the border, old boy!"
Despite the charade, Roberts' handprints were left imprinted on the car, and the three had all left footprints at the scene. In spite of all of the setbacks the saboteurs had faced during the operation, the bomb detonated just as planned and completely cut off power to the construction site in the early hours of Sunday, 10 February. However, with a wealth of evidence left at the scene and a witnessed rental car, the police swiftly identified and arrested Emyr Llywelyn Jones at his flat in Aberystwyth on the evening of 18 February, just over a week after the bombing.
Gellilydan
In accordance with the oath the trio had sworn before undertaking the sabotage, Emyr Llywelyn Jones refused to disclose his accomplices' identities during interrogation and hindered police efforts to identify them. Police searches of Emyr Llywelyn’s flat uncovered evidence including maps and photographs of the Tryweryn area, manuals relating to explosives, and correspondence with individuals in Ireland. Arresting officer Sergeant Glanmor Hughes stated that the evidence discovered amounted to what one "might expect to be in the possession of a person intent, or guilty, of having caused an explosion". On 21 February, Emyr Llywelyn appeared before the court in Bala to answer the charges against him and was represented by W. R. P. George, a nephew of former Prime Minister David Lloyd George. The courtroom was reported to be full, with many attendees present to show support for Jones, including a bus carrying sixty students from Aberystwyth.
W. R. P. George argued that the bombing was not “a criminal act in the common sense of the word”, a submission permitted by the chair of the bench and reported at the time to have caused concern among police. The chair subsequently ordered that the defendant be released on bail in his own recognisance of £100, on condition that he reappear in court on 14 March and reside at his family home in Llandysul in the interim. The trial received extensive sympathetic coverage in Welsh-language publications, including Baner ac Amserau Cymru. During a BBC Wales programme, Plaid Cymru president Gwynfor Evans stated that those responsible for the attack had his “full respect, sympathy and moral support”. Emyr Llywelyn’s trial continued in Bala throughout March, during which a range of forensic evidence and witness statements was presented to the court. Among the witnesses called to give evidence was Hugh Roberts, who had witnessed the trio in the snowdrift on the night of the attack. Roberts received threats after providing evidence in the trial and later recalled to the BBC in 2023, “I wish I hadn't had seen them, but I didn't have a choice. I was here at the wrong time.” On 29 March 1963, Emyr Llywelyn was summoned for sentencing at the Carmarthenshire Assizes, where he was convicted and sentenced to one year's imprisonment for his involvement in the bombing of the transformer.
On 31 March 1963, shortly after Emyr Llywelyn's sentencing, Owain Williams and John Albert Jones attempted to destroy an electricity pylon near the village of Gellilydan in protest. The pylon was located just two miles from the Trawsfynydd nuclear power station construction site, and the two men believed it connected to the Tryweryn construction site through Blaenau Ffestiniog. Given the pylon's close proximity to the village, the pair feared that a timed device would endanger any unaware locals, requiring them to detonate the explosives manually. It was also deemed too dangerous by the pair to attempt to acquire a new timing device. Despite planting gelignite explosives at the base of each of the pylon's four supports, only the first bomb successfully detonated, as its detonation destroyed the electrical circuit necessary to trigger the subsequent blasts. This resulted in the pylon failing to collapse as intended and simultaneously alerted the surrounding area of the attack. The saboteurs were forced to quickly escape the scene before they could be caught. While the pair escaped uncaught, the attack instigated fresh police investigations, which succeeded in turning up Williams' earlier accomplices from the Llithfaen quarry raid, Robert Williams and Edwin Pritchard.
Trial and imprisonment Following the arrest of Owain’s two earlier associates, statements were obtained that implicated him and directed police to his café in Pwllheli. This ultimately led to the arrest and conviction of both Owain Williams and John Albert Jones for their role in the bombings. Williams was the first to be arrested on 7 April 1963 and later claimed that police sought to coerce a confession by confronting him with his crying children, relating to the quarry raid, the transformer bombing, and the Gellilydan bombing. A police search of Williams’ flat uncovered a copy of the movement’s oath, newspaper clippings relating to the Tryweryn bombing and Emyr Llywelyn’s trial, and a homemade Free Wales Army (FWA) poster.