A former Sinn Fein activist in Newry has claimed party supporters are waging a violent hate campaign against him because of his repeated criticism of its activities - including its response to Barry McElduff's Kingsmill video.
But John McCabe, who had a window in his home smashed just before Christmas, has vowed that he won't be silenced by the attacks.
"It feels like I'm under siege, but I won't bow down to bullies," said Mr McCabe (52), who is involved in cross-community work in the city.
"I am on medication and I'm not sleeping properly, waiting for the next thing to happen, but they don't scare me and I will keep on saying what I think."
Mr McCabe, whose claims have been denied by Sinn Fein, has been an outspoken critic of his erstwhile colleagues on social media - no more so than in recent days after the party suspended its West Tyrone MP for three months.
It came after Mr McElduff posted a video of himself with a Kingsmill loaf on his head on the 42nd anniversary of the massacre of 10 Protestant workmen outside the south Armagh village.
Mr McCabe, who said he didn't believe the timing of the posting of the video was a coincidence, wrote on Facebook: "Sectarianism once again has been given the green light by the leadership of Sinn Fein in the North of Ireland."
He said the party had "rewarded Barry McElduff with a three-month waged holiday for keeping the sectarian faith by mocking the murders of 10 innocent Protestants at Kingsmill back in 1976".
He also posted: "RIP: The End of Sinn Fein's Respect Agenda; the Mask has Slipped."
He criticised the party's former Finance Minister Mairtin O Muilleoir for retweeting his colleague's video, though he called him 'Martin Miller'.
Mr McCabe said he believed the Kingsmill row had created the worst community relations in Newry and Armagh since the height of the Troubles.
"All they're doing is isolating Protestants in Bessbrook and that greater area," he claimed.
He said he believed most nationalists - including many Sinn Fein voters - were appalled by the Kingsmill controversy and wanted to reassure their Protestant neighbours that they shared their pain.
Last month Mr McCabe - who has been campaigning for the erection of a statue to Newry-born legendary Celtic manager Willie Maley - claimed in the Belfast Telegraph that republicans may have been blocking the plans because Maley was the son of a British soldier.
He said: "It wasn't long after the article appeared that my home was attacked. I can't directly link it to the story, but I'm convinced it was carried out by Sinn Fein Youth." A relative's home was also targeted.
Mr McCabe said his house in Newry had been attacked at least five times before, mostly with missiles, although there had been attempts to start fires too. He also said that he once fled the house after a gang of men tried to break in.
"They were obviously out to harm me and it was just by the grace of God that they didn't get me", he said. Mr McCabe was once an active member of Sinn Fein in Newry and wrote Press releases for the party. He said he had been arrested on "freelance" arms charges in the 1980s before he became aligned to the republican movement. He added: "I was never formally sworn in or anything like that. But if you ask me if I was supportive, I would have to say 'yes'."
He was questioned about the murders of Army corporals David Howes and Derek Wood in west Belfast in 1988, but never charged.
"I was drinking in a pub in Newry at the time, but a man in the video looked like me," he said.
"I was beaten in Castlereagh and Gough Barracks."
But Mr McCabe said that after relations with Sinn Fein soured he quit the party. "There was a whispering campaign and lies were spread about me on social media," he claimed.
"I just had the good sense to leave. I'd met a girl and wanted out. I'm not a dissident," Mr McCabe added.
He went to England to "get away from the hassle" but he was held under the Prevention of Terrorism Act and later released before returning home. He said he was currently working on cross-community projects with, among others, the Church of Ireland in Newry.
"And I don't think that sits too well with Sinn Fein, who talk about a shared space while I try to live it out," said Mr McCabe, who added that many nationalists agreed with his views on Sinn Fein.
He went on: "A lot of people stop me in the street to say they back me, though they are too frightened to speak out. But I'm not."
Sinn Fein denied having anything to do with the attacks on Mr McCabe.
The party said: "No one should be subjected to hate and harassment. Sinn Fein absolutely refute any involvement in any of the incidents in question. Anyone with any information regarding these incidents should contact the PSNI immediately."