ATHENS — A court in Athens on Tuesday sentenced two Greek anarchists who posted letter bombs to European leaders including German Chancellor Angela Merkel to 37 years in prison each.

Haralambos Hatzimihelakis and Panayiotis Argyros, both 23 and part of the Conspiracy of Nuclei group, were found guilty of “forming and being members of a terrorist” group at a special court in Athens.

They were found responsible for instigating a 2009 bomb attack on the homes of the Greek Interior Minister Panayotis Hinofotis and former Socialist minister Louka Katseli.

Conspiracy of Fire Nuclei is an anarchist group which has claimed responsibility for dozens of attacks since 2008.

A total of six members of the group, including the two men, were found guilty of extremist acts.

Georges Karayannides, 31, was sentenced to 20 years for “being part of a criminal organisation” and for being “complicit” in the attack against Katseli.

Three others — Panayotas Massouras, Alexandros Mitroussias, both 22, and Konstantina Karakatsani, 20 and the only woman, were all sentenced to 11.5 years in prison for “belonging to a criminal organisation” and for complicity in the Katseli attack.

A seventh member, Emmanuel Yiospas, was given two years and nine months for burglary, theft and falsifying documents.

Two others were acquitted by the special court, which has been sitting since January in Korydallos prison in an Athens suburb where most of the nine accused have been held.

The last of several bomb attacks claimed by the group caused extensive damage to a courthouse in Athens in December.

The group shot to international attention last November for a series of letter bombs to foreign embassies in Greece and to four European leaders — Merkel, French President Nicolas Sarkozy, Italy’s Prime Minister Silvio Berlusconi and European Commission head Jose Manuel Barroso.

One of the letter bombs, which contained gunpowder, ignited and lightly injured a courier company staffer in Athens, but most were intercepted by police.