An IRA man who was convicted of the Shankill bombing in which 10 people died, is back in prison after his early release licence was suspended.
Shankill bomber Sean Kelly is back in jail
NI Secretary Peter Hain said he had authorised Sean Kelly's return to jail after security information indicated he had become "re-involved in terrorism".
Kelly was one of two men who planted a bomb in a Shankill Road fish shop in 1993. Nine civilians died.
He was freed early from prison in July 2000 under the Good Friday Agreement.
Kelly was injured in the explosion and his IRA accomplice was amongst those killed.
Mr Hain said: "I am satisfied that Sean Kelly has become re-involved in terrorism and is a danger to others and while he is at liberty, is likely to commit further offences.
"On the basis of security information available to me, I have decided to return Sean Kelly to prison with immediate effect."
Mr Hain also warned that he would not hesitate to suspend the licence of other prisoners who were freed from prison early under the Agreement if they "presented a risk to the safety" of others.
It is understood Kelly was detained in north Belfast and is now in Maghaberry jail.
BBC Northern Ireland security editor Brian Rowan said he had been told that a "police dossier" on Kelly had been given to the secretary of state.
"The suggestion is that it details a build-up in activities which, I'm told, are in breach of Kelly's early release terms, as part of the Good Friday Agreement," said Mr Rowan.
"He had been photographed recently during disturbances in north Belfast but, I'm told, the arrest was not on the basis of any one incident.
"He is the first high profile republican to be returned to jail in this way. It comes at a time when the IRA is debating its future and with a statement due soon."
NI Secretary Peter Hain has suspended Kelly's licence
Sinn Fein assembly member Gerry Kelly said Mr Hain had made a "deplorable" decision.
He accused Mr Hain of "acquiescing to the demands of unionists and securocrats opposed to the peace process".
"This was a calculated decision that will increase tensions in north Belfast and elsewhere in the middle of the marching season. It was a cynical decision," he said.
However, North Belfast MP Nigel Dodds described the move as "welcome news".
"This development further damages the credibility of Sinn Fein who only a week ago praised Kelly and denied his terrorist links," Mr Dodds said.
"The many thousands of IRA victims will take some comfort from this belated move, but I challenge the government to act in all cases and not to be hamstrung by the fear of political repercussions."
During his trial, Kelly, from north Belfast, refused to recognise the court and declined to give evidence in his defence.
He received a total of nine life sentences.
It will be now for the independent Sentence Review Commissioners to consider Kelly's case and decide whether to revoke his licence.