A political firestorm swept through Spain yesterday after the Government released a notorious Eta killer from prison on “humanitarian grounds”, fearing that he was close to death after 114 days without eating.

To avoid angry crowds, the Government spirited Iñaki de Juana Chaos from the secure hospital unit in Madrid, where he was being force-fed, to a clinic in the Basque Country. He will be allowed to serve out the remaining year of his sentence at home under police supervision.

Hailed as a returning hero, de Juana was greeted by about 200 supporters as he arrived last night at a clinic near the Basque city of San Sebastian. “Iñaki, freedom!” they chanted, running alongside the ambulance. Riot police scuffled with a group of supporters who surged forward as de Juana was taken by wheelchair into the hospital.

Announcing the end of the hunger strike, a spokesman described de Juana’s release as the “achievement” of “thousands of men and women who have been fighting for months”.

The leader of the Popular Party, Mariano Rajoy, demanded the Prime Minister’s “immediate” appearance before Parliament to explain the decision. “Eta has made the Government buckle,” he said.

Acknowledging that the move would be controversial, Alfredo Pérez Rubalcaba, the Interior Minister, explained that he had freed the prisoner to prevent him from dying “in the next couple of weeks”.

“I have pondered this decision a lot,” a pained-looking Mr Rubalcaba said. “I have thought through the consequences of my decision and, perhaps more, of what would have happened if I had not taken it.”

He emphasised that de Juana had served his 18-year sentence for his role in the killing of 25 soldiers and policemen in the 1980s and was now in prison for making veiled threats in newspaper articles. “For many of us it will seem that he has spent little time in prison, but the fact is that he served the sentence imposed by the courts.”

The Government — and, by some indications, Eta — feared that de Juana’s death would trigger a new cycle in the conflict at a time that it had seemed headed for extinction.

In one of his greatest political gambles, José Luis RodrÍguez Zapatero, the Prime Minister, appears to have decided to weather the immediate political storm in order to prevent the conflict extending for another generation.

The decision nevertheless sparked fury among groups representing Eta’s 800 victims, with some reportedly calling the opposition Popular Party in tears. “The Government has surrendered to Eta,” the Association of Victims of Terrorism said. The decision to release de Juana on health grounds was a “macabre irony, given the state of those he murdered, mutilated, destroyed socially and psychologically”.

The police union lamented the “terrible news”, adding that if the decision were in its hands de Juana “would never leave the hospital alive”.

But there was relief in the Basque Country that a fresh cycle of violence had apparently been averted. The Basque Nationalist Party, which governs the region, called the move “advisable” and “legally impeccable”.

The case of de Juana has become a lightning rod for deep political divisions in Spain and has been hotly discussed since The Times published an unprecedented interview with him on February 5.

From his hospital bed he called for a resumption of the peace process, but expressed no remorse for his bloody past. The article was accompanied by a photo of de Juana looking emaciated after losing 28kg (4½st) in weight.

With the backing of Tony Blair and other leaders, Mr Zapatero’s Government embarked on talks with Eta after it declared a permanent ceasefire last March. The talks made scant headway and were ended after Eta exploded a bomb at Madrid airport on December 30, killing two Ecuadorean immigrants. The Popular Party has attacked the Government relentlessly over its talks with Eta, saying they were tantamount to surrender to terrorism. The Government has accused the Popular Party of hypocrisy, noting that it held talks with Eta during a 1998 ceasefire. Mr Rubalcaba said that the Popular Party had freed 20 Eta prisoners, many serving sentences for murder.

Doctors have told the Government that de Juana had only weeks to live, even if they continued to force-feed him. That was becoming increasingly difficult: supporters said that de Juana had managed to rip out a catheter three times on Tuesday.

Mr Rubalcaba said: “The State has to be humane even with those who did not act this way with their victims.” De Juana was due to be freed two years ago. To prevent his release, the Government had charged him with making terrorist threats in two articles he wrote from prison.

In November a court handed him another 12 years and seven months, prompting his hunger strike. Last month the Supreme Court overturned that sentence, giving him three years for glorifying terrorism.

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