MADRID, May 21, 2008 (AFP) - Spanish and French police detained late Tuesday the suspected leader of the Basque separatist group ETA, Javier Lopez Pena who is also known as 'Thierry', along with three other alleged members of the group in a joint raid on an apartment in the French city of Bordeaux.

The arrests were hailed in both countries Wednesday as a major blow against terrorism and the most significant operation against the group since 2004.

The following is a list of the main police operations against ETA, which has killed 823 people in its 40-year campaign for an independent Basque homeland:

- July 26, 2007: ETA's logistics chief, Juan Cruz Maiza Artola, is detained in Rodez in the south of France.

- October 3, 2004: The leader of ETA's political apparatus since 1992, Mikel Albisu, alias 'Antza', and his companion Soledad Iparragirre, alias 'Anboto', who managed the group's extortion network, are detained in Salies de Bearn in southern France.

- December 19, 2002: ETA's military leader, Juan Ibon Fernandez Iradi, alias 'Susper', is detained in the south of France. He escapes three days later and is recaptured in December 2003.

- February 22, 2001: Arrest at Anglet, near Biarritz, of Francisco Javier Garcia Gaztelu, alias 'Txapote', who assassinated 29-year-old city councilman Miguel Angel Blanco in 1997.

- March 9, 1999: The alleged chief of ETA's commandos, Jose Javier Arizkuren Ruiz, is held in Paris.

- March 29, 1992: ETA's military chief Francisco Mugica Garmendia, its political head Jose Luis Alvarez Santacristina, alias 'Txelis', and its logistics chief Jose Maria Arregui Erostarbe are detained in Bidart, France. This was the most significant police strike carried out against ETA to date, with the three main leaders detained in one blow.

- January 11, 1989: ETA's historical leader Jose Antonio Urrutikoetxea, alias 'Josu Ternera', is detained in Bayonne, France, just days after the group declared a ceasefire which led to failed peace talks with the government.

- November 1986: French police finds a weapons arsenal and extensive documentation regarding the activities and finances of ETA at a furniture factory in Hendaye, on the border with Spain, and detains ETA's suspected financial director, Jose Arrieta Zubimendi, alias 'Azkoiti'.

- April 1986: ETA leader Domingo Iturbe Abasolo is detained in the south of France. He is deported to Gabon and later to Algeria, where he died in 1987.