Sinn Féin MLA Máirtín Ó Muilleoir has said he stands over a claim that the RUC were involved in Michael Stone's deadly attack on mourners in Milltown Cemetery.
Three people were killed and more than 60 injured in March 1988 when UDA man Stone launched a gun and grenade attack at the funeral of three Provisional IRA members shot dead by the SAS in Gibraltar.
On Sunday, the former Sinn Féin finance minister tweeted from a memorial event for Thomas McErlean, who was among those killed at Milltown.
Fra McCann addressing commemoration in honour of Milltown hero Thomas McErlean. Thomas, who was just 20, died protecting mourners from the RUC-UDA attack on the funerals of the Gibraltar Three on 16 March 2018. A plaque was unveiled at his home today. #Crógacht @FramccannMLA pic.twitter.com/0WsF0Li27K
— Máirtín Ó Muilleoir (@newbelfast) March 18, 2018
Mr Ó Muilleoir said the 20-year-old died "protecting mourners from the RUC-UDA attack on the funerals of the Gibraltar Three".
However, former RUC assistant chief constable Alan McQuillan was among those who challenged the South Belfast MLA's claim.
Mr McQuillan said it was "yet another attempt to re-write history".
"I happened to be watching the helicopter coverage on that day," he said.
"Police officers got to Stone and arrested him as quickly as possible."
But Mr Ó Muilleoir is standing by his assertion.
"In the 1980s and early 90s the RUC was deeply involved in collusion with loyalist gangs," he told the BBC.
"Over the last few days we have commemorated Milltown, three heroes who saved many lives by defending mourners and pushing back Micheal Stone on that day.
The former Belfast mayor said the grenades and weapons used were secured by British army agent Brian Nelson.
"I know Alan well and admire his efforts to defend the RUC, he does it manfully," said Mr Ó Muilleoir.
"If he really wants to he should throw open the files and let the families see the truth of that day, that allegation is more than an allegation, it's a fact."
