The SDLP on Friday night hit back after Causeway Coast DUP councillors slammed a plan to honour a local gay rights activist who died of AIDS, claiming he was sympathetic to IRA terrorism.
Activist Mark Ashton, who was brought up in Portrush, became an influential figure in the Lesbians and Gays Support the Miners movement in London during the miners' strike in the 1980s.
Described as "a firecracker of a human being", Mark died through AIDS in 1987, aged 26.
A petition calling for a public memorial to the gay activist has gathered over 15,000 signatures, and Causeway Coast & Glens SDLP councillor Margaret McKillop has proposed a motion for the council to create a memorial to Mr Ashton and his work for the LGBTQ+ community.
But the idea has gone down badly with the council's DUP group, concerned at Mr Ashton's Communist Party links and at online suggestions he had sympathised with IRA terrorism.
A statement from the group said: "Concern has been expressed by Causeway Coast and Glens DUP Council Group at the campaign to erect a plaque/ memorial in memory of Mark Ashton who was born in Oldham and was brought up in Portrush, a former member of the Communist Party."
The DUP group added: "It is widely reported that he regularly liked to carry a Young Communist League banner featuring a rewrite of 'I do like to be beside the seaside' a reference to 1984 bombing of the Conservative Party Conference by the IRA.
"We are horrified and disturbed at a time when Causeway Coast and Glens Council have just completed a consultation into a permanent memorial to the six people murdered in the 1973 Coleraine bomb by the IRA; at the same time some are suggesting a memorial close by in Portrush to someone who reportedly gloated in the bombing in 1984 by the same terrorist organisation who attempted to wipe out the UK Government and British Cabinet."
Last night, an SDLP spokesman said that there was no evidence for the DUP claims about a pro-IRA bomb 'banner', other than a recently-edited Wikipedia page.
"If the DUP insists that it has been 'widely reported' that Mark Ashton carried a banner referencing the Brighton bombing, they should immediately provide evidence of it other than a Wikipedia Page that was edited to make the claim last week," a party spokesman said.
Former Communards pop star Richard Coles, now a Church of England vicar, described his late friend Mark Ashton to Radio Ulster's Talkback show.
"He was a remarkable person - a man of passionate convictions, and devoted himself to the causes he believed in.
"He was also really good fun - very naughty, and never in the least bit puritanical, as some activists can be. He just made you think that a better world was possible," Rev Coles told the BBC.
A plaque was dedicated to Mr Ashton in London, and a garden in memory of him was created in Paris.
The motion calling for a memorial is expected to be heard in April.