Fifteen Iraqi soldiers have been killed as they transported confiscated bombs to a disposal area, officials say.
The accident happened in northern Iraq, when one bomb exploded, igniting the other weapons and bombs, killing the soldiers on the truck.
They were driving to a vacant area in Bashika, east of Mosul.
The Iraqi army frequently undertakes controlled explosions in the area to dispose of confiscated weapons away from residential areas.
Mosul is one of the few remaining Iraqi cities where there is still routine insurgent violence.
On Thursday, a soldier and three policemen were shot dead.
Nationally, violence in Iraq saw a spike in August, with the highest number of violent deaths for more than a year.
Iraqi government figures showed that 393 civilians were killed that month, along with about 60 police officers and soldiers.