An 800-year-old religious relic, which was stolen from Christ Church Cathedral in Dublin six years ago, has been recovered by gardaí.

What is believed to be the heart of St Laurence O’Toole, the patron saint of the Dublin diocese, was found undamaged following an intelligence-led investigation and a search in the Phoenix Park.

The Church of Ireland Archbishop of Dublin, Dr Michael Jackson, welcomed the discovery of the relic, which he says has no economic value, but is a priceless treasure that links the cathedral with its founding father.

Assistant Garda Commissioner Pat Leahy, who is in charge of policing Dublin, will hand over the relic to the Archbishop at a service in Christ Church this evening.

The heart was stolen on 12 March 2012 by a thief who is believed to have hidden overnight in the cathedral.

It was stolen from inside an iron-barred case.

The thief also lit two peace candles on the Trinity altar in the cathedral before he left.

St Laurence O'Toole became Archbishop of Dublin in 1161 and was consecrated the following year at Christ Church Cathedral, but died in northern France in 1180.

His body was buried in Normandy but his heart was returned to Ireland and had been on display in the Chapel of St Laud in the cathedral until it was stolen.

The breakthrough in the garda investigation came in the last few weeks when two garda superintendents - one who had been involved from the start - received credible intelligence in relation to the relic.

A surveillance and search operation was set up and the relic was discovered hidden in the Phoenix Park.

Fingerprint and forensic tests have also been completed.

No arrests have been made.

The Dean of Christ Church Cathedral said the relic’s recovery is incredible and very exciting

Dean Dermot Dunne says he was dejected when it was stolen and he did not know what had happened to it.

He added that there had been speculation that it had left the country and it was news to him that the relic had not left Dublin.

Dean Dunne said he has taken possession of the relic and stored it in an inner safe in the Cathedral, but the official handover of the heart will take place this evening.

He said everyone was invited to the ceremony because it was significant for the people of Dublin.

He said the relic was intact and a photo of it would be going on the cathedral's Facebook page.

Dean Dunne added that he hoped a shrine to St Laurence will be built by November and the heart can be stored safely in the shrine.

Until then, he said, it would not be on public display.