DIRKOU, Niger — The heavily armed troops are positioned around oases in Niger’s vast northern desert, where temperatures routinely climb beyond 100 degrees.

While both Al Qaeda and the Islamic State have branches operating in the area, the mission of the government forces here is not to combat jihadism.

Instead, these Nigerien soldiers are battling human smugglers, who transport migrants across the harsh landscape, where hundreds of miles of dunes separate solitary trees.

The migrants are hoping to reach neighboring Libya, and from there, try a treacherous, often deadly crossing of the Mediterranean to reach Europe.