Officials say a homemade bomb has killed two people and wounded 13 others on a troubled southern Philippine island where Al-Qaeda-linked militants are active. Acting Sulu provincial Gov. Kadil Estino says the bombing late Saturday was carried out by the militant Abu Sayyaf group in retaliation for the killing of a member by the military in a clash three days earlier. Police Chief Glenn Roy Gabor in the provincial capital, Jolo, says the bomb was placed in front of a grocery store that is a favorite shopping place for Philippine marines. The shop was closed and most of the victims were bystanders in a nearby park. The Abu Sayyaf is on Washington’s list of terrorist groups and has been blamed for numerous kidnappings, beheadings and bombings.