A bomb hit the car of a vice mayor in Isabela City in Basilan island province, killing three security escorts of the vice mayor and injuring five others.

In the other incident, a bus from Polomolok in South Cotobato to General Santos City was hit by a blast that injured 18 passengers, South Cotobato Police Director Senior Superintendent Jose Briones said.

Authorities said the Isabela City explosion appeared to be political in nature while the Polomolok blast was most likely the work of extortionists.