The IRA's history of splits

The 2005 peace accord between Sin Fein, The Unionist Party, and Tony Blair was rushed based on the 7/7 bombings.

BBC News
The attacks against the military and police in Northern Ireland are part of a pattern in Irish history in which dissident groups split away from mainstream Republican organisations to maintain their dream of a united Ireland.

The question always arises as to whether these groups themselves then take over as the main flag-bearers.
The Provisional IRA did so in 1969 when it broke away from what became known as the Official IRA. There were ideological differences, but the main motivation was that the Provisionals felt that not enough had been done to protect Catholic communities in Northern Ireland.

Although "provisional", they proved remarkably permanent.
The two groups claiming the latest attacks - the Real IRA for the killing of the two soldiers and the Continuity IRA for the policeman - are themselves breakaways from the Provisional IRA, whom they accuse of abandoning the aim of an all-Ireland republic by ending its armed campaign in 2005 and joining the new power-sharing Northern Ireland government.