Last summer, Islamic State leader Abu Bakr al-Baghdadi sent close associates to Libya to explore closer cooperation with local jihadists.

Once there, they found al Qaeda-aligned groups were already starting to cooperate to take advantage of Libya’s unique cocktail of chaos and a diffuse weapons arsenal. Instead of fighting rival jihadists as it had done in Syria, Islamic State decided to co-opt them and to bring the fight to Libya, said a security official with knowledge of Libyan jihadist groups.

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