Family members and followers of Philippine dictator Ferdinand Marcos have gathered for a vigil at his tomb a day after his secrecy-shrouded burial at the country's Heroes' Cemetery triggered protests.

Marcos' widow Imelda, clad in black, thanked supporters and local officials of Marcos' northern home province who traveled by bus to pay their respects. She said they had given her family strength as they kept the hope for nearly 30 years to have him buried at the national cemetery.

Enraged pro-democracy activists say the decadeslong debate over the ex-president's final resting place was far from over and protested across the metropolis on Friday. They gathered Saturday to plan more protests.

President Rodrigo Duterte, who gave the go-ahead for the burial, appealed for calm.