A prominent Belfast republican has said Special Branch officers followed him on holiday to Spain and attempted to recruit him as an agent, offering a huge sum of money if he informed on dissidents.

Paul Carson (44) from Ardoyne said he was pursued by two officers for over a mile in the Costa del Sol. He said he refused their requests and hurled abuse at them.

As dissident activity increases, the security services have massively stepped up their campaign to recruit informers. Last month, a member of the 32 County Sovereignty Movement, was approached while on holiday in Italy.

Carson, a former republican prisoner, claimed he was told money would be "no object" if he worked with them to prevent Oglaigh na hEireann, a Real IRA splinter group, from killing policemen. He said the same Special Branch officers had previously tried to recruit him last month in Belfast International Airport as he prepared to board a flight to Glasgow for a Celtic match.

"I was brought into a small room where these two plain-clothes guys questioned me about my involvement in opposing loyalist parades and in Concerned Families Against Drugs (a group which marches on alleged drug-dealers houses). They said I was well-respected in the area. They said dissidents were going to shoot a police officer coming from a community meeting and I could use my clout to stop it."

Carson said he was asked to spy on Oglaigh na hEireann, the paramilitary group which last week tried to killed a police officer in Belfast with an under-car bomb and was responsible for leaving a 600lb bomb in Forkill, south Armagh, last month.

"I told the police I'd no such influence with dissidents and anybody claiming otherwise was a gobshite," he said. Carson claimed the same Special Branch officers then approached him on 8 October when he was holidaying in the Grangeville Oasis apartments near Mijas on the Costa del Sol.

"They asked me to talk to them in a restaurant down the road, that nobody would know. I told them to f*** off." Carson said the officers kept following him, shouting that they knew he'd carried out murders years ago for which he'd never been convicted.

Carson said he had immediately logged the attempts to recruit him,was pursuing the matter with his solicitor and would be contacting the Police Ombudsman. "It's important to make these approaches public so the situation is crystal clear," he said.