Summary
In Aden, Yemen's most cosmopolitan city, the masked Islamist gunmen seem to have burst onto the streets from some other world.
Three months ago, local fighters and a Saudi-led alliance of Arab states recaptured Aden from the Houthis and brought President Abed Rabbou Mansour Hadi's government back to the city from exile in Saudi Arabia.
The Islamists are hardly new to Yemen: for years, Yemen's rural tribal areas have sheltered one of the most powerful regional branches of Al-Qaeda, which the United States has targeted in a secret drone war, in alliance first with Saleh's government and then with Hadi's.
Al-Qaeda's strict Sunni ideology makes it natural enemies of the Shiite Houthis, and the Houthis say Hadi's government and Al-Qaeda have become de facto allies on the battlefield.
On Oct. 6 in Aden it staged its biggest attack against Hadi's government and his Arab allies with another quadruple suicide bombing that killed at least 15 people including four Emirati soldiers.
Hadi's government says it is taking steps to get armed youths off the streets, including plans to incorporate into its forces some 5,000 members of the so-called Southern Resistance, part of a separatist group that helped drive the Houthis out of Aden.
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