Russia has also joined a Baghdad-based intelligence cell along with Iran, Iraq and Syria that has provided information on Islamic State targets.

And several European countries staff an intelligence cell there, unprecedented in U.N. peacekeeping, that analyzes input from unarmed drones, sensor-equipped attack helicopters and special forces.

Last week the Defense Ministry reported the detention of a businessman heading a "terrorists' intelligence cell" who it said "participated actively" in the Chibok abductions.