In December 1972, widow Jean McConville, 37, was dragged from her Belfast home by a group of IRA men as her 10 children tried to cling to her.
She was executed. The Irish Republican Army (IRA), admitted to the killing in 1998, falsely accusing her of being an informant for the British army. An investigation by Northern Ireland's Police Ombudsman said there was no evidence that she was an informant.
Her remains, including a skull with a single gunshot wound to the back of the head, were finally discovered in 2003 -- more than 30 years after she disappeared -- buried on an Irish beach.
arrested in Dublin Wednesday night for questioning over the 1972 murder. He insists he had nothing to do with it.
Michael McConville, one of the slain woman's sons, has told BBC Radio that he and his siblings know the names of some of the IRA men who abducted their mother, but "I wouldn't tell the police."
"Me or one of my family members or one of my children would get shot by these people. People think this (IRA threat) has gone away. It hasn't," McConville said. "Splinter groups of the IRA would class you as an informant and shoot you."
"I never told anyone who I saw. I still haven't," he told BBC Radio 4.
Mr. McConville said he was happy to see the police were now "taking this case very seriously."
He recalled the night the IRA men burst into his home and pulled his mother away from him and his siblings, who tried desperately to cling to her.
"My mother was in an awful state, because the IRA had took her from a bingo hall the day before and they had her for a few hours, and they beat her up. The army had found her, wandering about the streets, disorientated -- didn't know where she was," he told the BBC, explaining why he and his siblings were so distressed when the same men came to take his mother away the next day.
Mr. McConville said IRA men grabbed him off the street about a week later as he walked to his grandmother's house and took him away, "because I knew the ones, some of the ones who had come in and took my mother away, because they didn't have masks on."
He said they covered his head and drove him to a house, strapped him to a chair and beat his legs and arms with sticks. He said the men held a gun to his head and threatened to shoot him, then stabbed him in the leg with a pocketknife before turning him lose with a warning; "if you tell anything about the IRA, we'll come back and we'll shoot you, or we'll shoot one of your family members."
McConville, who said fear for his own young family's safety keeps him from identifying the men he saw abduct his mother, told the BBC he knew his mother was dead a couple weeks after she was taken, when an "IRA man" came and dropped off her wedding rings at the family home.