Updated

The Philippine defense secretary and military chief of staff are visiting a Philippine-occupied island in the South China Sea to assert the country's claim to the heartland of a disputed area where China is believed to have added missiles on man-made islands.

The trip led by Defense Secretary Delfin Lorenzana on an air force C-130 aircraft Friday to the island Filipinos call Pag-asa will likely infuriate China.

Beijing claims virtually the entire South China Sea and has aggressively tried to fortify its claims to the consternation of rivals. It has cemented its foothold with seven artificial islands now feared to have surface-to-air missiles.

President Rodrigo Duterte scrapped his plan to fly to Pag-asa, also known internationally as Thitu, to raise his country's flag on June 12, Philippine Independence day.