DETECTIVES investigating the murder of Kevin McGuigan have arrested a 60-year-old this morning.
He was detained in east Belfast in connection with the murder.
The suspect has been taken to the Serious Crime Suite in Antrim for questioning.
The DUP has raised the prospect of Sinn Féin being excluded from the Stormont executive following McGuigan’s murder.
On Thursday, detectives said Provisional IRA members were involved in the 53-year-old’s murder last week when he was shot dead outside his Comber Court home in the Short Strand district.
Sinn Fein have rejected the police statement saying the IRA “had left the stage”.
DUP leader Peter Robinson said he would have discussions with other Executive parties “about tabling the necessary exclusion motion in the assembly and asking the secretary of state to intervene in circumstances where the evidence points to the IRA being involved”.
He said he had engaged in an initial discussion with the PSNI Chief Constable George Hamilton.
Mr Robinson said that before the return of the assembly from recess, his party would seek a further update from Mr Hamilton “to establish his conclusion regarding those responsible and the role of those in the republican movement who are associated with Sinn Féin”.
“As I indicated in my press briefing last week there can be no place for terror and murderous activity on our streets and republicans cannot be in the executive in circumstances where this murder was the work of the Provisional IRA,” he added.
DUP MP Gregory Campbell said that independent assessment was needed on the IRA’s status and that the party would also be seeking a meeting with the Northern Ireland Secretary Theresa Villiers.
His party’s Finance Minister Arlene Foster said it was a “very serious time for power-sharing in Northern Ireland”.
She said what was needed was to establish “reality and fact” to determine if the Provisional IRA was still operating behind the scenes.
“It is very concerning to think that so-called units may still be in existence or may be stood up at a time when they’re needed to deal with so-called internal matters,” she said.
“Murder is murder and it cannot be in any way at the heart of what we do in Northern Ireland.”
Police said on Thursday that an organisation called Action Against Drugs, whose members include members of the Provisional IRA, were responsible for Mr McGuigan’s killing.
Sinn Féin North Belfast MLA Gerry Kelly said the IRA no longer existed and asked for a meeting with Mr Hamilton.
He described the PSNI’s statement as “contradictory”.
“The IRA has gone, it has left the stage, it made a statement in July 2005, saying it was gone,” Mr Kelly added.
He said the police assessment that members of the Provisional IRA were involved in Mr McGuigan’s murder was wrong.
“In that same statement the chief inspector said that the AAD, the Action Against Drugs was the organisation he believed was involved,” he said.
“I am a republican. I am saying this is a criminal gang. I think I may have the credibility to be able to know the difference.”
Sinn Féin’s Martin McGuinness said those who killed Mr McGuigan and Jock Davison were criminals and “must be brought to justice”.
TUV leader Jim Allister said it was “time for unionists who work the Belfast Agreement to face up to reality”.
He said it was time to show Sinn Féin the “exit door from government”.
“I accept the reality that a senior police officer has said that it is his belief that current IRA members were involved in this heinous murder,” he said.
“Now if there are current IRA members, then there’s a current IRA.
“If the IRA exists then Sinn Féin has a paramilitary wing, and what place in government is there for a party with a paramilitary wing, that’s how elementary this is.”