Republicans, anti-imperialists and supporters of political prisoners gathered in Derry on Saturday to demand the immediate release of Niall Sheerin, who remains imprisoned in Maghaberry despite having completed the custodial part of the sentence handed down by a British court.

The protest outside Strand Road Police Station was organised in support of Niall Sheerin and against the Multi-Agency Review Assessment (MARA) process, a modern-day form of internment being used to keep republican prisoners behind bars beyond their sentences.

Séamus Fitzsimons of the Irish Republican Prisoners Welfare Association (IRPWA) pointed out that Niall has fully served the custodial sentence imposed upon him, but remains imprisoned.

In May, he was shamefully denied precious time with his dying father as a result of MARA.

Mr Fitzsimons said the MARA process was “directed by the hand of MI5 and British intelligence” and “operates as a shadowy body designed to ensure that Republican prisoners face sentence extensions based on secret, unchallengeable assessments”.

He said the system had turned prison sentences into rolling, open-ended detention and called for “an immediate end to the policy, an end to the weaponisation of the parole system and the immediate unconditional release of Niall Sheerin”.

He described the continued imprisonment of Niall as a calculated attempt to break the spirit of political prisoners and inflict collective punishment on their families, and called on Republicans, anti-imperialists, human rights advocates and the wider community to oppose what he described as a “resurgence of executive internment”.

The IRPWA has launched a national campaign for Niall’s release, arguing that the Parole Commissioners have adopted the powers of indefinite detention and accused the British state of using the prison system as a tool of political suppression.

“The continued imprisonment of a man who has completed his sentence is a draconian decision based on British policy in Ireland. It is a calculated assault on the basic tenets of justice and due process,” the IRPWA said.

In a statement demanding his release, the organisation said:

“Niall Sheerin is a political prisoner.

“No amount of State-sponsored labels or judicial overreach can strip him of his republican identity or his commitment to the struggle for a 32-county socialist republic.”

The IRPWA said that by keeping Sheerin imprisoned beyond his court-mandated release date, the British state had abandoned even the appearance of fairness and was using imprisonment to target republican prisoners and their communities.

Anti Imperialist Action Ireland has also backed the campaign. “This is internment,” they said. “All Republicans state that they are opposed to internment whether it was in 1971 or in 2026. But how many are willing to speak out now in support of Niall Sheerin and other Republican POWs held in occupied Ireland, many through the draconian use of internment by remand.”