Abu Sayyaf (/ˌɑːbuː/ /sɑːˌjɔːf/; Arabic: جماعة أبو سياف‎‎; Jamāʿat Abū Sayyāf, ASG; Filipino: Grupong Abu Sayyaf) is a Jihadist terror group based in and around Jolo and Basilan islands in the southwestern part of the Philippines, where for more than four decades, Moro groups have been engaged in an insurgency for an independent province in the country. The group is considered very violent, and was responsible for the Philippines' worst terrorist attack, the bombing of Superferry 14 in 2004, which killed 116 people.The name of the group is derived from the Arabic abu (Arabic: أبو‎‎) ("father of"), and sayyaf (Arabic: سيّاف‎‎) ("swordsmith"). As of 2012, the group was estimated to have between 200 and 400 members, down from 1,250 in 2000. They use mostly improvised explosive devices, mortar