King Juan Carlos joined scores of politicians and others on Monday to mourn Manuel Fraga, one of the key players in Spain's transition to democracy, who died on Sunday after suffering a cardiac arrest. He was 89.

Galicia declared three days of mourning for its former conservative premier who governed for more than 15 years and was instrumental in helping modernizing the then-poor northwest region. "It is a shame," King Juan Carlos was overheard saying as he visited Fraga's Madrid home along with Queen Sofia and one of their daughters, Princess Elena.

Prime Minister Mariano Rajoy, who is also from Galicia, was the first politician to visit Fraga's home where he died. "He was one of the greatest politicians of the century," the Popular Party (PP) leader said.

The founding president of the conservative PP suffered a cardiac arrest after suffering from a respiratory infection since the beginning of January. He was accompanied by his close family when he died.

Before the Transition, Fraga had occupied a variety of roles in Francisco Franco's dictatorial regime, including the post of tourism and information minister. "He knew that it was necessary to join the democratic system," said former Socialist Deputy Prime Minister Alfredo Pérez Rubalcaba.

As a lawmaker, Fraga remained active on Spain's political scene until the spring of 2011, when he scaled back his activity after suffering a fall in his Madrid home.