Loyalist paramilitaries were blamed yesterday for attacking a councillor's home hours after giving the Government assurances that they had ended all violence.
Mr Danny O'Connor, a former Northern Ireland Assembly member, opened fire after a gang vandalised his mother's car.
Fearing the loyalists were planning to bomb their home in Larne, Co Antrim, the SDLP representative fired four shots from a legally held gun.
Mr O'Connor's mother, Mrs Rosaleen O'Connor, said: "So much for Paul Murphy and the UDA ceasefire. It wasn't even 45 minutes old when these scum came and attacked my home and my car.
"They have been at this for years and years. They attacked my husband and I buried him two years ago. They attacked my son, pipe-bombed him and threatened him and I buried him a year ago.
"Am I going to have to bury my other son myself?"
No-one was injured during the trouble at Churchill Road, but a car belonging to Mrs O'Connor had tar poured over it.
Mr O'Connor said he believed his life was under threat. "There was one fella who looked to be in the act of throwing something - I don't know if it was a stone or a pipe bomb - but at the time, when you have to react to something like that, everything just seems to happen instantaneously," he told BBC Radio Ulster.
"I was really scared because I thought it might have been a pipe bomb because my late brother had been pipe-bombed.
"I fired four quick shots over the top of their heads - they ran away. I was really afraid for my life, to be honest with you."
SDLP leader Mr Mark Durkan defended Mr O'Connor's decision to open fire. "Danny O'Connor and his family have suffered continuous assault, intimidation and abuse from loyalist paramilitaries and their supporters since Danny first became involved in the SDLP."