The Russian Defense Ministry says the accident took place on April 30 near the village of Bolshaya Tura. It said a civilian truck hit a land mine while a group of military engineers was preparing for a cleanup operation in the area.
The village of Bolshaya Tura is close to the military warehouse where a blaze on April 29 sparked explosions that continued for several hours.
None of the civilians in the truck were injured in the explosion.
The sappers were hospitalized; one of them is reportedly in a very serious condition.