Fifteen people were injured, two seriously, by a blast outside a college near the presidential palace in Manila, Philippine police said on Tuesday.
Manila's police chief said they were investigating whether the blast, which occurred about 300 metres from the palace gates, was caused by a grenade.
"A safety lever of a hand grenade was found," said Geary Barias.
The blast occurred at around 4:30 pm. (Reuters)
Blast near Philippine presidential palace wounds 15