The head of the PSNI says the Provisional IRA is no longer involved in terrorism.

George Hamilton says that while some of the the provisional IRA structures remain in place, its purpose has radically changed since the 1990s.

It follows a number of meetings with political parties in the North today about the investigation into the murder of Kevin McGuigan.

The Chief Constable also says he has no information to suggest orders to shoot down Mr McGuigan were sanctioned at a senior level in the republican movement.

However Hamilton says he is still sticking by the lead detective's claims, that members of the republican terror group may be linked to the shooting.

Sinn Féin insists the IRA was not involved in the killing of Kevin McGuigan.

Party MLA Gerry Kelly spoke to reporters outside the talks this morning:

Sinn Féin's President Gerry Adams TD has unequivocally addressed allegations of IRA involvement in the murder, saying: "the IRA was not involved."

The Louth TD hit out those who he says have "opportunistically and cynically seized on the killing of Kevin McGuigan."

In a statement last night Gerry Adams said: "The killing of Kevin McGuigan was wrong and those who were involved in it are criminals who do not represent republicanism."

Mr Adams said that there were parties who had seized on the killing "in a deliberate effort to undermine Sinn Féin's mandate ... and the peace process."

He went on to say: "In July 2005 the IRA left the stage. Its leadership ordered an end to the armed campaign ... (a)ll of this was done as part of a genuine initiative to build a just and lasting peace and in support of the full implementation of the Good Friday Agreement."

The statement came after the PSNI last night said they suspected IRA involvement in the killing.

First Minister Peter Robinson says he cannot work with Sinn Féin if IRA involvement is proven.

The debacle could have implications for the Northern Assembly, with the DUP saying it will hold talks with the other parties about excluding Sinn Féin from the power-sharing executive.

Sinn Féin Councillor Daithi Doolan says that 'elements' are attempting to undermine the peace process: