Twelve people were killed and 60 injured Friday when a suspected bomb blast ripped through a night market in the home city of Philippine President Rodrigo Duterte, officials said.
Duterte was in Davao City, 960 kilometres south of Manila, when the explosion occurred at the open-air market, but was safe monitoring the situation at a police station.
"Based on initial investigation, police found a shrapnel from a mortar-based improvised explosive device," Communication Secretary Martin Andanar said in a Manila radio interview.
While no one has claimed responsibility for the blast, presidential spokesman Ernesto Abella urged the public to "refrain from reckless speculation and avoid crowded places."
"There is no cause for alarm, but it is wise to be cautious," he said.
Rows of stalls selling food, clothes, toys and other goods make up the night market, located just across a university and a posh hotel. Some stalls also offer massage services at the popular hangout among local residents and tourists.
Chief Superintendent Manuel Gaerlan, a regional police director, said 10 people were killed on the spot due to the explosion, while two more died while being treated in hospital.
The explosion occurred after Abu Sayyaf, an Islamist terrorist group, warned of attacks amid a military offensive against them on the southern island of Jolo.
Troops have killed at least 30 Abu Sayyaf militants in the offensive since the weekend, while 15 government soldiers died in the hostilities, according to the military.