The 20 prisoners, aged from 22 to 71, will make up four relay teams for the run.

Two Prison Service staff teams, including deputy governor Claire Graham, and another team from the South Eastern Health and Social Care Trust based in Maghaberry, will also take part in the marathon event inside the prison.

Maghaberry Prison governor Tracy Megrath said the staff and prisoners are running to raise funds for the Cancer Fund for Children charity.

“This will actually be the third Belfast Marathon held in Maghaberry Prison. We started this in 2023 and it’s been an annual event for the staff and prisoners ever since,” she said.

“The prisoners have been on a structured programme since January this year — as well as the fitness aspect they’ve been learning about good nutrition and diet.

“Several hundred pounds has already been raised through donations from staff and fellow prisoners, and we expect the final total to top £1,000.”

She added: “The Prison Service challenge and support all those who are sent to us by the courts, and through various rehabilitation projects and purposeful activity we promote a sense of achievement and prepare them for the return to their community.”

Cormac McMullan, community fundraising and engagement lead with the Cancer Fund for Children, said they were “incredibly grateful” for the support.