A loud explosion rocked the grounds of the Philippine presidential palace on Monday, but there were no known casualties, witnesses said.
HT Image"The authorities are investigating the cause of the explosion," Press Undersecretary Isabel de Leon told the agency by telephone.
The blast was clearly heard around the Malacanang palace compound in central Manila.
ABS-CBN television reported from the scene that a device appeared to have exploded inside a garbage bin outside one of the buildings in the compound.
The explosion was in front of a building inside the palace grounds, an agency correspondent said.
The area has been sealed off by police and presidential security guards.