Though it claims to have an Islamist agenda, the Abu Sayyaf has become better known for banditry. Since it turned kidnapping into a lucrative trade, the group has beheaded five foreigners, including their latest victim, German sailor Jurgen Kantner. Other victims include:
- Guillermo Sobero, 40, a Peruvian-born American businessman. He was snatched together with American missionaries Martin and Gracia Burnham from the Dos Palmas resort in Palawan province in May 2001, and killed on June 19. He was the first foreigner to be executed by the Abu Sayyaf.
- Bernard Then, 39, a Malaysian engineer. He was taken from a resort in Sabah, with Ms Thien Nyuk Fun, 50, a restaurant manager, in May 2015. A ransom of 30 million pesos was reportedly paid for the two but only Ms Thien was released. Mr Then was beheaded on Nov 17, 2015.
- John Ridsdel, 68, a Canadian former mining executive and journalist. He was seized from a high-end marina in Davao province in September 2015. His head was found inside a plastic bag on April 25, 2016.
- Robert Hall, 51, a former welder, also a Canadian. He was taken along with Mr Ridsdel. He was killed on June 13, 2016. Norwegian Kjartan Sekkingstad, 56, was also abducted with them but he was freed after his captors received US$638,000 (S$897,000).
The Abu Sayyaf had released dozens of hostages, but only when ransom is paid.
In 2014, it abducted German couple Stefan Okonek and Henrike Dielen from a yacht in the southern Philippines. They were released six months later after a ransom demand of US$5.1 million was paid.
The Abu Sayyaf is believed to still be holding at least 19 foreigners and seven Filipino hostages.