[1] In 1956 Altamirano was jailed thrice, during the wave of repression that took place after the killing of Anastasio Somoza García.
He became a member of the central leadership of the Confederación General del Trabajo (independiente) trade union centre in 1962.
[2] In December 1970 POSN held its constitutive congress, adopting the name Communist Party of Nicaragua and electing Altamirano as its general secretary.
[1][3] Under Altamirano's leadership the Communist Party took an anti-Sandinista stance, isolating itself from the broader revolutionary movement.
[1] In 1973 he founded the Central de Acción y Unificación Sindical trade union centre.
CAUS organized a strike on factory workers in March 1980, provoking reaction from the new Sandinista government.
[8] Altamirano was arrested along with other Communist Party and CAUS leaders on October 21, 1981 and sentenced to seven months imprisonment for violating the Public Order Law.