MANILA - President Rodrigo Duterte on Monday visited a Catholic church in Jolo, Sulu where twin explosions the day before left 20 people killed and 100 others wounded.

Surrounded by coffins of those who perished, Duterte spoke before a crowd that gathered near the ruins of the cathedral, based on photos released by his former special assistant, Bong Go.

LOOK: President Duterte visits Jolo, Sulu blast site (Photo from ex-SAP Bong Go) @ABSCBNNews pic.twitter.com/mIs1DkujbF

— Dharel Placido (@dgplacido) January 28, 2019

Duterte was "angered" and "disappointed" after the blasts, Presidential Spokesperson Salvador Panelo said earlier in Manila.

"Of course he was so angry, for one. For another, he is so disappointed that despite the movement to tread the path towards peace and development, there are still some forces in that region who sow terror and kill and murder people," Panelo told reporters.

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Panelo said there could be "lapses in security" and that the President was awaiting results of investigations into the incident.

"[The martial law] is effective but this incident is isolated by the way so we have to investigate how it happened. There may be lapses in security. There is no other conclusion to reach. If you have security there and there is one or two bombings

The Islamic State has claimed responsibility for the blasts, which prompted the Philippine National Police to place its forces nationwide under the second highest alert. The highest alert was raised in Metro Manila.

The Jolo bloodshed came a week after a majority of voters approved the creation of the Bangsamoro, a new region giving Muslims in the south more control over their own affairs it.

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