The Guardian newspaper has apologised to a woman who said she had been raped by a member of the IRA over an article written about her by former columnist Roy Greenslade.

Mairia Cahill, great-niece of prominent Belfast republican Joe Cahill, says she was sexually abused as a 16-year-old by alleged IRA member Martin Morris.

Mr Morris, who denied all wrongdoing, was acquitted of rape when the case against him collapsed.

Mr Greenslade wrote a 2014 column in The Guardian which said that the BBC, which investigated Ms Cahill’s claims, “were too willing to accept Cahill’s story and did not point to countervailing evidence.

“That is not to say that she was not raped.

“Nor does it negate her view that the IRA handled her complaint clumsily and insensitively.”

Ms Cahill alleges that the republican movement’s response to her claims was to subject her to an IRA interrogation.

She also accused Sinn Fein of engaging in a ­cover-up and waging a campaign to question her integrity since she waived her right to anonymity.

Recently, Mr Greenslade wrote in the British Journalism Review that he backed the IRA’s armed campaign while he was working as a journalist during the Northern Ireland conflict.

The Guardian, in an update attached to Mr Greenslade’s original 2014 piece, said: “In March 2021, Mairia Cahill contacted the Guardian to complain that this article had been published and without disclosure of the writer’s political affiliations.”

It added: “The Guardian’s readers’ editor considered the complaint and concluded that the columnist ought to have been open about his position.”

After concerns raised by a reader following publication of the article in 2014 that Mr Greenslade had not disclosed his Sinn Fein sympathies, he started to declare his writing during the 1980s for the party’s newspaper, An Phoblacht, including at the end of two more blogs relating to Ms Cahill.

The Guardian added: “He now says he regrets that he did not add it retrospectively to this piece and offers his ‘sincere apology for failing to disclose my own interests’.

“Columnists are hired for their opinions but the readers’ editor considered that here the writer’s political position should have been indicated openly.

“The lack of disclosure was especially unfair to a vulnerable individual, and the Guardian has now apologised to Ms Cahill.”