The defendants were said to have been arrested by security operatives with knives, daggers and swords.
The Irigwe Development Association has refuted allegations its people were behind the Rukuba road killing.
Governor Simon Lalong has relaxed the 24-hour curfew imposed on Jos North local government area.
The Plateau governor said the perpetrators acted on their own and did not represent any religious, ethnic or social interests.
The JNI has called on the government at all levels to be decisive in sending a message of deterrence to criminal elements and fish the Rukuba Road assassins.
Governor Simon Lalong of Plateau, alarmed by the rapid spread of violence killing dozens of people, has held a closed-door meeting with security heads and religious leaders.
The coordinated response is to protect the community and boost public confidence in the affected areas.
Exams were scheduled to commence on Monday August 16.
The Plateau CAN chairman condemned recent attacks in Bassa, Riyom, Jos South and Barkin Ladi Local Government Areas.
Security personnel have stepped up patrols in Jos metropolis to maintain peace.