The incident occurred Friday morning at Rumuekpe under Emohua Local Government Area.
Available information has it that the explosion, which also consumed vehicles, emanated from the tapping point of a pipeline.
It was gathered that a driver had loaded one of the buses at the location with crude oil packaged in bags.
Preparing to move the petroleum product away from the scence, he started the vehicle engine which triggered a blast.
The man and others nearby are among the fatalities.