Two of four suspects detained in connection with a double bank heist near Kozani in northern Greece on Friday, are believed to be behind a series of bank robberies carried out to finance the creation of a new urban guerrilla group, Kathimerini understands.

Police had in 2011 issued arrest warrants against the two for membership of the terrorist organization Conspiracy of the Cells of Fire after physical evidence was found at suspected hideouts in Volos, central Greece, and Kallithea in Athens.

The two allegedly maintained contact with Christos Tsakalos, Giorgos Nikolopoulos and Damiano Bolano, who were convicted last year over a series of bloodless bomb attacks in 2009 and 2010.

One of the two suspects, a 24-year-old identified only as G.M., had been previously detained during a protest rally in Syntagma in February 2011 after he tried to shoot at police with a bow-and-arrow. He has since been dubbed the “Syntagma archer.”

The same person is also believed to have taken part in a fatal bank robbery on Paros last year, after which 29-year old Tasos Theofilou was charged with the murder of taxi driver Dimitris Michas, who was shot dead while trying to stop the gang from escaping after the heist. Theofilou was also charged for membership of Conspiracy of the Cells of Fire.

Investigators have said that the island raid – like others being planned – was aimed at raising funds for terrorist activity. In a letter posted on the Internet after the Paros robbery, G.M. had allegedly expressed solidarity with the perpetrators.

Meanwhile, the police has linked the same two suspects with the Agricultural Bank robbery in Florina, northern Greece, last November, while reports suggest that authorities also believe them to be behind the bombing at The Mall in Maroussi, northern Athens, last month.

Four men, aged between 18 and 25, were arrested following two almost simultaneous holdups on branches of ATEbank and Hellenic Postbank in Velvento, near Kozani, on Friday morning.

Between eight and 10 people were involved in the two robberies, according to witnesses who said they saw masked assailants using sledgehammers to smash through the glass fronts of the banks before threatening staff with heavy weapons, believed to be Kalashnikov assault rifles. The perpetrators netted more than 200,000 euros in the raids.