A republican has given the Sunday Tribune extensive details of how suspected paedophile Liam Adams was heavily involved in a Sinn Féin cumann in west Belfast which met two streets away from where his brother Gerry lived.

The details disclosed to us by the republican prompted Sinn Féin on Friday to finally admit that far from being expelled from the party in Dundalk, Liam Adams remained involved in the party four years later – in the heart of the Sinn Féin president's constituency.

The republican who contacted us last week denounced "the dreadful saga of deceit, misinformation and cover-up engendered by Gerry Adams" about his brother's involvement in Sinn Féin.

The republican stated: "I feel let down, and guilty too for having kept quiet." The republican insisted that Liam Adams had never been "dumped" from the party: "He was an active and founder member of the Lower Andersonstown Sinn Féin cumann by the name of 'Cumann Mheon na Fuiseoige' that met on a weekly basis in the Felons' Club in Lower Andersonstown."

The republican said Liam Adams' involvement was common knowledge in Sinn Féin circles in West Belfast: "There never was any attempt to operate in ­secrecy."

The republican named the wife of a senior Sinn Féin official who is extremely close to Gerry Adams as a fellow member of the cumann with Liam Adams. Other republicans later contacted the Sunday Tribune with the names of other Sinn Féin members of that cumann.

The republican stated that Liam Adams canvassed for Sinn Féin in Belfast and was involved in many fundraising events in the city for the party. The republican added that it was inconceivable that the Sinn Féin president didn't know of his brother's involvement in Cumann Mheon na Fuiseoige.

He added that Sinn Féin membership was granted only following a lengthy period of vetting locally and by the national leadership.

Gerry Adams claimed he only found out of Liam's involvement in this cumann last Thursday.

On Thursday night, the Sunday Tribune had emailed Sinn Féin a list of questions about Liam Adams and raised, for the first time by the media, the possibility of his involvement with the party in Belfast.

In a clear damage limitation exercise, Sinn Féin stated on Friday that Liam held several positions, including chairman, of an Andersonstown cumann "before the cumann dissolved".

A death notice placed by the cumann in the Irish News shows it was still active in 2004.

Paddy Power has actually opened betting on who is likely to succeed Adams. Surprisingly, Mary Lou McDonald is the 4/5 favourite, followed by the North's regional development minister, Conor Murphy at 5/1.

Martin McGuinness drifted out on Friday from 5/2 to 6/1. Pearse Doherty and Toireasa Ferris are 8/1, junior Stormont minister Gerry Kelly is 12/1 and Caoimhghín Ó Caoláin is 33/1

Paddy Power has opened a book on whether Peter Robinson or Gerry Adams will be first to resign or be removed as a Northern party leader. Robinson is the 2/7 favourite, Gerry Adams is 9/4.