Havana ? A prominent Cuban government opponent imprisoned for allegedly revealing state secrets was suddenly freed Friday, two years shy of completing his 15-year sentence, a fellow human rights activist said.

Francisco Chaviano, now 54, was released on parole after serving 13 years, three months and three days, said Elizardo Sanchez of the Cuban Commission for Human Rights and National Reconciliation.

Chaviano was president of the Cuban National Council for Civil Rights when he was arrested in May 1994. He was sentenced behind closed doors by a military court about a year later for allegedly revealing state secrets while documenting the cases of rafters who disappeared or died trying to leave Cuba. Chaviano denied revealing state secrets, and his supporters said no defense evidence was presented during the trial.