source: AFP; BBC News
actor1: Islamic State (West Africa) - Lake Chad Faction
actor2: Civilians (Nigeria)
location: Maiduguri
notes: Around 13 December 2019, ISWAP killed four aid workers who they held in hostages since July 2019. The event occurred in an unspecified location [coded: Maiduguri (Borno, Maiduguri)].