Although the armed forces continue to make inroads against their strongholds, Abu Sayyaf remain a force to be reckoned with. For years, the militants have maintained a reign of terror in the Southern Philippines, and beyond. Here is some of what is known about the Islamic State-affiliated organisation:
Abu Sayyaf — which translates as ‘bearer of the sword’ or ‘father of the swordsmith’ — is a relatively small group that emerged from the long-running Muslim separatist insurgency that has claimed more than 120,000 lives in the Southern Philippines since the 1970s. Their current size is estimated at just 400.
The group was established in 1991 with funds gifted by a relative of Osama bin Laden. However, in recent years the group has switched its allegiance from Al Qaeda to the so-called Islamic State (IS).
It is believed that as IS continues to lose ground in the Middle East, it is eyeing the Southern Philippines as a new stronghold. Foreign jihadists have already begun to arrive, often via Malaysia. (See links below.)
Abu Sayyaf’s strongholds are the small islands of Jolo and Basilan in the deep south of the Philippines.
Abu Sayyaf has been involved in the kidnapping of hundreds of people since the 1990s. Using fast boats and hi-tech navigational equipment, the militants raid resorts, coastal communities and port areas.
They have been known to travel hundreds of miles from their strongholds, even operating in Malaysia’s Sabah state. A recent kidnapping raid on the island of Bohol was unsuccessful.
In recent years Abu Sayyaf has focused its operations on piracy, abducting Indonesian, Vietnamese, Korean and Malaysian sailors on fishing vessels and cargo barges.
While their greatest profit comes from kidnapping foreigners, locals have also been kidnapped and ransomed for smaller amounts.
Currently, it is believed Abu Sayyaf is holding six Vietnamese, five Malaysians, seven Indonesians, a Dutchman and seven locals.
A single kidnapping can earn a fortune. The group claimed it received more than $5 million to release a German couple abducted off their yacht in 2014. A video showing the cash was shared online.
Earlier this month, Defence Secretary Delfin Lorenzana revealed that the employers of two kidnapped Indonesian sailors paid a ransom of 20 million pesos ($400,000) for their release.
The group was responsible for the worst terrorist attack in Philippine history — and the worst maritime terror atrocity in the world — when it bombed Superferry 14 in September 2004, which claimed 116 lives.
From 2002-2014, the US deployed special forces to train and assist Filipino troops, which led to the killing or arrest of many Abu Sayyaf leaders.
US assistance was scaled back after the Pentagon concluded that the group, which originally had about 1,000 fighters, had lost the ability to launch international attacks.
Shortly after taking office last year, President Duterte announced a military offensive to “destroy” the group. After a slow start, inroads are beginning to be made against the group.
The difficulty of combatting the group is due to a combination of the group’s mastery of the islands’ mountainous and jungle-clad terrain and support from local communities.
This local support is thought to be more down to the group’s wealth, rather than any widespread ideological backing. It is thought this wealth has also helped the group buy off local police and other local authorities.
Surviving former hostages have reported that despite their declared status as holy warriors, some members of the group seemed barely aware of the Koran, and many were shabu users.
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