(Reuters) - Here are some facts on left-wing urban guerrilla groups in Greece, following a wave of parcel-bomb attacks on European government targets.

* FIRE CONSPIRACY CELLS:

-- Police suspect that one of two men arrested Monday is a member of the Fire Conspiracy Cells, a group that has staged several attacks on government targets over the past year and describes itself as an anti-state organization.

-- In May 2009, it claimed responsibility for two small time-bombs that exploded at the construction sites of two new police stations.

-- In September 2009, it said it had planted a small bomb outside a government building in the northern city of Thessaloniki. The bomb went off hours after a blast outside the Athens bourse claimed by another cell, Revolutionary Struggle.

-- In January 2010, Fire Conspiracy Cells claimed responsibility for a small bomb blast outside parliament.

-- Last March, the group claimed three small blasts in Athens: at a police detention center, the office of the far-right Golden Dawn group, and the home of a leading member of the Pakistani community. It vowed to step up attacks.

-- Police have arrested 17 people this year suspected of being members of the group.

* REVOLUTIONARY STRUGGLE:

-- The Revolutionary Struggle aims to overthrow the existing economic and political order in Greece and is opposed to the influence of globalization and capitalism on Greek society. Analysts have said that the group shares much of its ideology with the Fire Conspiracy Cells and have said that there may have been some co-operation between the two groups.

-- Revolutionary Struggle emerged in September 2003 with a bomb attack on a court in Athens, about a year after the capture of most of the leaders and senior members of the urban guerrilla group November 17, which had killed more than 20 Greek and foreign diplomats -- notably British defense attache Brigadier Stephen Saunders, shot and killed in his car in June 2000 -- in its 27-year existence. November 17 was named after the date of a crushed 1973 student uprising against the then-ruling military junta in which at least 13 students were killed.

-- In 2006, the group attempted to kill a minister and in 2007 it launched a rocket-propelled grenade at the U.S. embassy in Athens, causing minor damage but no injuries.

-- The group reappeared weeks after police killed a teen-ager in December 2008, which sparked the nation’s worst riots in decades. It claimed responsibility for shooting at riot police guarding the Culture Ministry, wounding a 21-year-old officer.

-- Revolutionary Struggle has claimed responsibility for an attack on a police bus and a failed bomb attack on Royal Dutch Shell’s headquarters in Athens, in 2008. In March 2009, it claimed two bomb attacks at Citibank branches in Athens.

-- The group has also said it was behind a blast at the Athens bourse in September 2009 which damaged the building.

-- Greece charged six suspected members of Revolutionary Struggle in April, over a series of bomb attacks.

* REBEL SECT:

-- The Rebel Sect emerged in February 2009 in a gun and grenade attack on an Athens police station. Weeks later, two hooded gunmen fired dozens of shots at a TV station in southwestern Athens, causing no injuries.

-- The Rebel Sect usually claims responsibility for its raids, in discs sent to the media. In its statements, the group has said it targeted police, politicians, lawyers and journalists.

-- In June 2009, the Rebel Sect claimed responsibility for the killing of a Greek anti-terrorism policeman in Athens. He was shot several times at close range. It was the first deadly attack since the country’s 2008 riots.

Sources: Reuters/Jane’s