Malacañang on Saturday assured the public that the explosion in Quiapo is not connected to the ongoing ASEAN Summit in Manila.
Presidential Spokesperson Ernesto Abella said security for the summit is in place.
"The incident is not in any way connected or directed to the ongoing ASEAN Summit. We assure our people that security measures are in place in today's event and ask the public for their full undestanding and cooperation in this regard," he said in a statement.
A homemade pipe bomb exploded along Quezon Boulevard, near the Quiapo Church in Manila Friday night, injuring 13 people.
Two people were seriously hit, with one losing a leg and another suffering severe injuries in the buttocks.
A gang war in the area is one of the motives seen behind the explosion.