Two former allies of Defense assassinated president killed , military says . Military says pair were plotting against government ; some fear military plans coup . President Joao Bernardo Vieira assassinated 69 in attack on presidential palace . Former West African colony has a history of military coups .
Two former allies of Guinea-Bissau 's assassinated president killed , military says . Military says pair were plotting against government ; some fear military plans coup . President Vieira assassinated March 2 in attack on presidential palace . Former Portuguese colony has a history of military coups .