In the early hours, assailants threw a grenade into a group of sleeping people inside the camp in the village of Nguetchewe, said district mayor, Medjeweh Boukar. The camp is home to around 800 people, he said.
The village is located in the Mozogo district, close to the Nigerian border in the Far North region.
Boukar was informed by residents that 15 had died. A security official confirmed the attack and the death toll. The wounded were taken to a nearby hospital, they said.
"The attackers arrived with a woman who carried the grenade into the camp," Boukar said, adding that women and children were among the dead.
Over the past month there have been twenty incursions and attacks by suspected militants, Boukar said.