HAVANA Cuba (AP) -- Eloy Gutierrez-Menoyo, who went from rebel commander fighting alongside Fidel Castro to a foe launching commando raids against the island before settling inside Cuba as a moderate, pro-dialogue dissident, died early Friday. He was 77.

Gutierrez-Menoyo died of a heart attack at 5:30 am at a Havana hospital, his wife Flor Ester Torres Sanabria told The Associated Press. Funeral plans were not yet known.

Gutierrez-Menoyo had lived permanently in Cuba since August 2003, after visiting the island during a family vacation and deciding to stay for good. Cuban authorities allowed him to remain despite his frequent criticisms of the government, but his immigration status was apparently never resolved.

The tall, slender man with long, wispy white hair and wire-framed spectacles had hoped to open an office on the island of his Cambio Cubano movement - but the dream was never realised. Nearly blind and hard of hearing, Gutierrez-Menoyo was seen occasionally in Havana at meetings involving moderate Cuban exiles.

Until his health began to fail him in 2010, Gutierrez-Menoyo frequently spoke out against the communist government, but in measured tones that kept him out of jail.

After Fidel Castro retired due to ill health in February 2008 and his brother Raul formally replaced him as president, Gutierrez-Menoyo expressed disappointment that Cuba's communist system remained unchanged.

"Cuba cannot continue to corner itself, trying to convince the world that there is democracy here when a one-party system will never be a democracy," he lamented.

Formed in Miami in 1992, Cambio Cubano was seen as a centrist group, promoting dialogue and reconciliation among Cubans of all political stripes, including officials in Castro's government. But some members of the exile community considered it soft and politically accommodating.

Born December 8, 1934, in Madrid, Spain, Gutierrez-Menoyo was the son and brother of men who fought against the Spanish dictator General. Francisco Franco.

One of his brothers died in combat in Spain as a member of the Spanish Republican forces. The family moved to Cuba in 1945 and another brother, Carlos, was killed in March 1957 during an attack on the presidential palace of Cuban strongman Fulgencio Batista.

Gutierrez-Menoyo, who had opposed Batista's government from the early 1950s, participated in the same attack. Later he formed and commanded the Second Front of Escambray, a rebel group that operated alongside but independently of guerrilla forces Castro led.

After the Cuban revolution's January 1959 victory, Gutierrez-Menoyo's Second Front was incorporated into the new government's Revolutionary Army, but its senior officers were not granted positions of authority.

Although he had arrived in Havana as one of the triumphant "Commanders of the Revolution," Gutierrez-Menoyo quickly broke with Castro and by 1961 was in exile in Miami helping form Alpha 66, an armed commando group dedicated to the violent overthrow of Castro's government.

In December 1964, Gutierrez-Menoyo returned to Cuba with an armed band in hopes of launching an uprising, but they were captured after a month.

Gutierrez-Menoyo spent 22 years in Cuban prisons, losing vision in one eye and hearing in one ear. He was freed in 1986 through a petition of the Spanish government after an international campaign for his release.

He went into exile, first briefly to Madrid, and then a year later to Miami, where he ultimately adopted a position of peaceful dialogue with Castro's government and founded Cambio Cubano.

He even met with Castro in 1995 - an encounter that was apparently never repeated.

A former wife, Gladys, and their three sons together, live in Miami. His daughter by an earlier marriage, Patricia Gutierrez-Menoyo, lives in San Juan, Puerto Rico, where she runs a publishing house.