MADRID (AP) — The Basque militant group ETA is announcing that it has "completely dissolved all its structures," in a letter sent to Basque institutions and civil society groups.

In the letter, published by Spanish online newspaper eldiario.es on Wednesday, ETA says it acknowledges its responsibility in failing to solve the Basque "political conflict."

ETA, whose initials stand for "Euskadi ta Askatasuna" — or "Basque Homeland and Freedom" — killed 853 people in its armed campaign to create an independent Basque state in northern Spain and southern France.

 Founded in the midst of Gen. Francisco Franco's regime, the group grabbed global headlines when it killed the dictator's anointed successor, Prime Minister Luis Carrero Blanco, in 1973.

The decision, ETA said in the letter, "doesn't overcome the conflict that the Basque Country maintains with Spain and with France."