The decision by a Spanish mass murderer to relocate to Ireland has turned into a classic police and media hunt for a man who wants to slip quietly into obscurity.

Unfortunately for Jose Ignacio de Juana Chaos, an ex-member of Eta, the Basque terrorist group fighting for an independent nation in the north of Spain, his choice of friends has got him into some very hot water.

The ex-convict gave his address to the Spanish Embassy in Dublin, during an application to renew his passport, as that of James Monaghan, a former director of the Provisional IRA’s weapons development “engineering department”.

Monaghan, along with Niall Connolly and Martin McCauley – the so-called Colombia Three – was found guilty in Bogota of training the Marxist guerrilla group Farc in IRA-style combat techniques and sentenced in 2004 to 17-year prison terms.

But the men escaped and returned secretly to Ireland. They have all been interviewed by Irish police but no moves have been made to extradite them to Colombia, in spite of warrants issued via Interpol.

De Juana Chaos, 52, was released from prison in Spain in August after 21 years in prison for the murders of 25 people in the 1980s at a time when he was a leader of an Eta cell in Madrid.

Public opinion, fuelled by media coverage, was bitterly opposed to his release, especially when it emerged that he was to take up residence in an apartment block where a number of Eta victims were living.

Last year he prompted further outrage during a hunger strike he was staging to protest about his incarceration. Under sentencing guidelines in 1987, when he was given 3,000 years for his role in the deaths of three soldiers, a rear-admiral and 12 military policemen, he had to serve just 18 years.

He gave an interview to The Times, accompanied by a photograph which purported to show him shackled to a prison hospital bed where he was being force-fed.

A Spanish judge, Eloy Velasco, has now asked Interpol to find de Juana Chaos in Ireland. He is being sought in connection with a letter he wrote upon his release from prison in which he expressed opinions which breach a Spanish law of “making an apology for terrorism”.

The crime, if proven, could result in a further custodial sentence for de Juana Chaos. But the ex-prisoner is apparently in no hurry to make his current whereabouts known and rumours are sweeping Ireland and Spain, with sightings of him having been reported in Dublin, Belfast and even South Armagh.

The former Eta prisoner gave Monaghan’s address in Killester, a Dublin suburb, as his own for the purposes of his passport application.

Spanish media have been camped outside the house, but the only interviews conceded to the reporters were by an angry Monaghan, who told them to clear off.

One Madrid newspaper has allegedly hired a team of private detectives, presumably in a bid to claim a scoop by beating the authorities to finding de Juana Chaos.

El Mundo newspaper, quoting Spanish security sources, said that the fugitive has been living in Belfast under the care of “prominent IRA” members.

The story has the potential to create difficulties for Sinn Fein, which has been seeking to put greater distance between itself and the Provisional IRA. The hunt for de Juana Chaos, in the company of James Monaghan, is – for the party – an unwelcome reminder of the close links once forged between Eta and the IRA.

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