A suicide bomb teacher accidentally blew himself and his students into smithereens after using live explosives in his belt.
The extremist was demonstrating how to use a deadly belt at a camp north of Baghdad when he inadvertantly set off the device, instantly killing himself and those around him.
In total the blast killed 22 insurgents and wounded a further 15, according to local police.
The teacher was thought to be a recruiter for a faction of Sunnis dedicated to destroying the Shia-dominated Iraqi goverment.
Local officials said eight surviving militants were arrested as they tried to escape the scene.