Colonel Gaddafi's Libya supplied weapons to the IRA
Serving police officers from NI went to Libya in the past year to help train its police, the BBC has learned.
A superintendent has arranged for training to be delivered in Libya and the UK for Libyan officers.
The Northern Ireland police officers are seconded to the UK's National Policing Improvement Agency (NPIA).
The PSNI said the Policing Board was informed in December 2008 of the deployment of an officer to Libya and the NIO approved it in January 2009.
"At all times the police service acted in an open and transparent manner," it said.
The NIO said "all the legislative requirements were met" in approving the secondment.
During the Troubles, Libya supplied guns and explosives which the IRA used to kill police officers.
Police said a chief inspector/temporary superintendent spent a number of days in Libya last November to assess training needs.
Based on his recommendations, an inspector was part of a tactical command course between 12 January and 2 February.
The NPIA website lists Superintendent Kevin Smith - who has served as a police officer in Northern Ireland for 24 years - as having arranged training for Libyan officers in Libya and the UK.
It also has details of a PSNI sergeant taking part in a training event for Libyans at the national police training centre in Bramshill in November 2008.
In a statement, the PSNI said: "As is the case with most other police services in the UK, we currently have a number of PSNI officers seconded to the National Policing Improvement Agency.
"There are agreed statutory processes on the international deployment of all police officers."
Some relatives of IRA victims have renewed their attempt to receive compensation from Libya following the release of the Lockerbie bomber, Libyan man Abdelbaset Ali al-Megrahi.
The DUP's Nigel Dodds is involved in that process.
He said it was "totally inappropriate and offensive" that PSNI officers were selected to provide training "given the very recent history of what the Libyans have done in terms of the annals of terrorism in Northern Ireland".
"Whoever made that decision, whoever thought that was the right way to proceed, must be living in a different world and different planet," he added.
"Until this matter of compensation and Libyan redress towards the victims is addressed, then this is an area that needs to be put on hold."
However SDLP policing spokesperson Alex Attwood said the DUP position was contradictory.
"The DUP say that they are prepared to sit in government with Sinn Fein because Sinn Fein now accept the rule of law and have renounced terror.
"For the DUP to now create a storm about helping Libya change its policing practices when Libya now also accepts the rule of law and renounces terror is contradictory and misleading," he said.
Ulster Unionist Basil McCrea, a member of the Policing Board, said he was shocked by the news.
"Somebody knew that these officers were going to Libya and somebody knew that was a very difficult political decision and they absolutely would have known that the Policing Board should have been informed."
TUV leader Jim Allister said approving the move showed "utter disregard to the history and deep sensitivities felt over Libya".
"Given the magnitude of this gaffe I would call on Nigel Dodds to join with me in calling on Ian Paisley Junior to resign from the Policing Board," he said.
However, former British ambassador to Libya, Oliver Miles, said the training move was not unexpected.
"If you go back to Tony Blair's first visit to Libya in 2004 one of the very first things that came out of that was a statement about co-operation in the military field, in security," he said.
"It doesn't at all surprise me that should involve a police element."
NPIA has confirmed that a number of Police Service of Northern Ireland officers have been involved with training the Libyan police over the past two years.
It also said officers from a range of UK police services have trained the Libyan police.
The training was arranged in response to a request for support from the Home Office and the British Embassy in Tripoli.