Key Takeaways:

1. Three al Qaeda affiliates—Jabhat al Nusra, al Qaeda in the Arabian Peninsula (AQAP), and al Qaeda in the Islamic Maghreb (AQIM), issued a joint eulogy for Afghan Taliban emir Mullah Akhtar Mansour on May 29. A U.S. airstrike killed Mullah Mansour in Balochistan, Pakistan, on May 21. Al Qaeda affiliates al Shabaab and al Qaeda in the Indian Subcontinent (AQIS) were not signatories to this joint statement nor to the August 2015 joint eulogy for the late Taliban emir Mullah Omar. AEI’s Critical Threats Project assesses that this is likely because of the weak relationship between Jabhat al Nusra and al Shabaab and AQIS.
2. Islamist militants, likely ISIS Wilayat Aden-Abyan, planted improvised explosive devices (IEDs) in at least two mosques in Aden before Friday prayers on May 27. Yemeni security forces found and cleared the bombs. ISIS has carried out mosque attacks in Yemen before, notably in Sana’a, but has generally restricted its targets in Aden to government, military, and security targets. The targeting of mosques, if confirmed, would indicate a new campaign for ISIS in Aden, designed to exacerbate tensions between northern and southern Yemenis and possibly spark sectarian divisions in the city. [See a recent post on AQAP’s loss of al Mukalla and sign up to receive CTP’s Yemen Crisis Situation Reports by email.]
3. ISIS is consolidating its forces in Sirte as Libyan armed groups advance into its control zone from the east and west. These offensives will likely stop before they reach ISIS’s stronghold, however. ISIS will conduct explosive attack campaigns in an effort to slow or halt the offensives. Competition between rival Libyan militias will also compromise counter-ISIS operations as they converge on Sirte. [See CTP’s backgrounder on forces in Libya and a forecast of ISIS’s courses of actions in Libya.]