A Greek far-left hitman in serious condition after a 52-day hunger strike was urged Monday to end his protest by his victims' families as the government accused him of "blackmail".

Dimitris Koufodinas, formerly the top assassin for the defunct November 17 extremist group, is seeking a transfer from a high-security prison in Domokos, central Greece, to Korydallos prison in Athens to be near his family.

His partner and mother of his son Angeliki Sotiropoulou has warned he is "borderline comatose" and doctors at a hospital in the city of Lamia, where he has been receiving intensive care for nearly a month, over the weekend warned that his health had "seriously deteriorated."

The relatives of Koufodinas' 11 victims on Monday urged him "to withdraw his demands and continue to live."

"His death will not bring any of our loved ones back," they said in a joint statement.

Supporters of Koufodinas have in recent weeks staged several protests and vandalism raids on ministers' offices.

Dozens of police have been stationed at Lamia hospital, and security has been reinforced around other potential targets including police stations and the offices of politicians and magistrates.

Government spokeswoman Aristotelia Peloni on Monday said Koufodinas was "requesting preferential treatment" and attempting to "blackmail" the authorities.

"He chose to place his life in danger," Peloni told reporters.

The dispute has split the Greek legal establishment. On Monday, over 40 judges and magistrates protested against a statement put out by their union last week, which urged the authorities to "reconsider" their stance and take "all legal measures to protect his life and health".

Hundreds of lawyers and intellectuals have signed petitions calling on judicial authorities to respect Koufodinas' rights.

Dubbed 'Poison Hand' by Greek media, Koufodinas was the main hitman of the far-left Greek extremist organisation November 17 that was dismantled in 2002.

He is serving multiple life sentences, having been convicted of 11 killings.

November 17 launched dozens of attacks between 1975 and 2000 that killed 23 people, including the CIA station chief in Athens, several prominent Greek businessmen, Turkish diplomats and a British military attache.

One of Koufodinas' victims was Pavlos Bakoyannis, a lawmaker who was the father of Athens Mayor Costas Bakoyannis and brother-in-law to Prime Minister Kyriakos Mitsotakis.

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