President Rodrigo Duterte is saddened by the death of several soldiers and injuring of others after the C-130 military plane they were aboard crashed in Sulu on Sunday, Malacanang said on Monday.

In a televised press briefing, Presidential Spokesperson Harry Roque said Duterte is waiting for the result of the investigation into the plane mishap before making any conclusion regarding the defense capacity of the country amid allegations of defective military equipment.

Last month, the Armed Forces of the Philippines' newly-acquired black Hawk helicopter also crashed in Tarlac, killing six soldiers.

"The President and the entire Filipino people are really saddened because we have soldiers who died because of this incident. But just like what I've said, the President said that we have to wait first for the formal investigation before we make the conclusions," Roque said.

At least 50 individuals, including 47 soldiers and three civilians, died and 49 soldiers were injured in the crash in Patikul, Sulu.

Duterte is set to visit on Monday the injured soldiers who have been treated in a hospital in Zamboanga City.

Roque said Defense Secretary Delfin Lorenzana has ordered an investigation. Celerina Monte/DMS