Filipino security forces have reportedly killed more than 40 jihadists during a five-day battle in the southern Philippines. The jihadists “claimed links with” the Islamic State, according to Reuters:

Philippine security forces killed as many as 42 Muslim rebels claiming links with Islamic State and captured their stronghold during five days of fighting in the mountains of a southern island, an army spokesman said on Friday. Three soldiers were killed and 11 wounded when the forces seized the bastion of an affiliate of Jemaah Islamiah, a Southeast Asian network of Islamist militants, in the province of Lanao del Sur.

The “affiliate” of Jemaah Islamiyyah (JI), traditionally seen as al Qaeda’s branch in Southeast Asia, was likely a splinter of the group that emerged in 2014 and pledged allegiance to Abu Bakr al Baghdadi and the Islamic State shortly after his announcement of the caliphate. Abu Bakar Bashir, the spiritual leader and co-founder of JI, left the group and formed his own Islamic State-loyal group, Jemaah Ansharut Tauhid.

However, Bashir’s two sons and several other leaders left and formed their own group, Jemaah Ansharusy Syariah. According to the Jakarta Post, more than 50 percent of Bashir’s followers abandoned him and joined Jemaah Ansharusy Syariah. According to its leader, it is directly part of al Qaeda’s global network now. (See LWJ report, Islamic State launches suicide assault in Indonesia’s capital.)

Other groups loyal to the Islamic State in the Philippines and the wider Southeast Asia region includes Katibat Ansar al Sharia, Katibat Marakah al Ansar, Ansar Khilafah in the Philippines, the Mujahidin Indonesian Timor, and a portion of or the entirety of the Abu Sayyaf Group, another group that was traditionally loyal to al Qaeda. (See LWJ report, Philippines-based jihadist groups pledge allegiance to the Islamic State.)

Caleb Weiss is a contributor to FDD's Long War Journal.

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