Meanwhile , Abu Sayyaf Group had started out on their own by 1991 under the leadership of the elder Janjalani brother , Abdurajik . By 1995 they had been active in large scale bombings and attacks in the Philippines , and also had become associated with Ramzi Yousef ( of the 1993 World Trade Center bombing , the 1994 Philippine Airlines Flight 434 bombing , and the foiled 1995 Operation Bojinka ) , and also with Jemaah Islamiyah ( al-Qaeda 's southeast Asia associated branch led by Hambali ) . At some point in the early 1990s , the younger brother Khadaffy Janjalani had also joined Abu Sayyaf , as a teenager , and was eventually imprisoned by the Philippines government
Philippine Airlines Flight 434
Philippine Airlines Flight 434
Khadaffy Janjalani