'OPERATION OGRO' IS THE TAPED ACCOUNT OF THE FOUR BASQUES WHO CAME TO MADRID, LIVED IN THE CITY FOR ABOUT A YEAR, CAREFULLY PICKED THEIR TARGET, ADMIRAL LUIS CARERRO BLANCO (WHOM THEY CONSIDERED THEIR KEY ENEMY IN THE SPANISH GOVERNMENT AFTER GENERALISSIMO FRANCISCO FRANCO), AND ASSASSINATED HIM ON DECEMBER 20, 1973, BY DYNAMITING HIS CAR. THE ACCOUNT DESCRIBES THE INFORMATION ABOUT BLANCO'S HABITS THAT BECAME THE BASIS FOR THE PLANNING OF THE ASSASSINATION. THE DAILY LIFE OF THE FOUR BASQUES IN MADRID DURING THE PLANNING IS PORTRAYED. THE ANALYSIS AND REJECTION OF A PLAN TO KIDNAP BLANCO IS OUTLINED, AND THE PLAN TO BOMB BLANCO'S CAR IN FRONT OF THE MADRID CHURCH, SAN FRANCISCO DE BORJA, IS DESCRIBED IN DETAIL. EVENTS OF THE SUCCESSFUL ESCAPE PLAN ARE ALSO RECOUNTED. THE APPENDIXES CONTAIN COPIES OF DOCUMENTS AND PUBLICATIONS ASSOCIATED WITH THE ASSASSINATION PLAN AND EVENT. (RCB)