The Philippine president has withdrawn the ceasefire with communist fighters after they failed to reciprocate. An insurgency has been going on in the country since the 1960s.
President Rodrigo Duterte announced the decision on Saturday after the guerrillas failed to meet his imposed deadline for declaring their own truce.
The newly elected Duterte had initially called for the ceasefire on Monday. When the Maoist rebels killed a government militiaman two days later, the president then ordered the insurgents to agree to their own ceasefire by Saturday.
"If I don't get the word from you, then I will lift the order of ceasefire," Duterte said at the time.
On Saturday, he released another statement confirming that the unilateral ceasefire was to be lifted and that all security forces should be on high alert.
Philippine soldiers in training. Duterte had earlier announced a ceasefire between the government and rebel forces
Hope for peace?
The militiaman who was killed was returning from a security mission along with his colleagues when he was ambushed by a group of rebels.
The Philippines has been dealing with political violence since the 1960s, when Maoist rebels first launched an insurgency that has claimed about 150,000 lives.
A self-described left-wing politician, Duterte has hoped to mend relations between Manila and the Maoist fighters.
The two sides had earlier agreed to resume peace talks in Norway next month, although it was not clear how they'd be affected by the scrapping of the ceasefire.
blc/rc (AP, dpa)