A middle-aged man and woman were last night being questioned by PSNI detectives in connection with the UVF murder of six Catholic men in a pub in Loughinisland, Co Down, in June 1994 as they were watching a World Cup game between the Republic of Ireland and Italy.
Police arrested a 45-year-old man and a 38-year-old woman in connection with the attack by two UVF gunmen on the Heights pub in Loughinisland in which six people were killed and five wounded.
The gunmen opened fire with automatic rifles and then escaped in a waiting car. The UVF admitted the attack but no one has been convicted for the killings. It is understood that the two arrested are from the Belfast area.
Those who died were Adrian Rogan (34), a scrap-metal contractor and father of two; single farmer Daniel McCreanor (59); father-of-four Eamon Byrne (39); his single brother-in-law Patrick O'Hare (35); Barney Green (87); and Malcolm Jenkinson (53), a father of three and a building contractor.
They were all from the general area of Loughinisland.
The murders caused Irish and international anger and revulsion, and shocked manager Jack Charlton and the Irish team when they learned of the killings after their victory over Italy in the Giants Stadium in New Jersey.
The UVF said the killings were in retaliation for an INLA attack in the Shankill earlier that week in mid-June which resulted in three deaths, including those of senior UVF members Colin Craig and Trevor King.
A memorial to the victims was erected outside the Catholic church across the road from the Heights bar in 1995.
The Loughinisland families in a statement yesterday welcomed the arrests and implied that this development was prompted by a complaint they made to Police Ombudsman Nuala O'Loan about the police handling of the investigation.
"It would appear that the attention of the Police Ombudsman's office has infused fresh endeavour into what is now a 12-year-old inquiry.
"The families hope that this arrest operation will result in charges and convictions but will await the outcome of these arrests before making further comment," they added.
Sinn Féin South Down Assembly member Caitríona Ruane said the families must be supported in gaining justice for "this horrendous tragedy has left deep scars on them".
SDLP MLA Margaret Ritchie said that while it would be wrong to speculate on whether or not this is a definitive breakthrough, any development in the inquiry must be welcomed.