The officials further added that the incident took place on Tuesday afternoon in Nawzad district.
Provincial governor spokesman, Omar Zwak confirming the report, said at least 14 militants including a Taliban commander killed following the blast.
Mr. Zwak further added that the militants had gathered to attend a training on how to create homemade improvised explosive (IED) when the incident took place.
Zwak said a Pakistani national who was in charge of the IED making training was also among those killed in the explosion.
The Taliban militants group has not commented regarding the report so far.
Taliban militants use improvised explosive device (IED) as the weapon of their choice and frequently target Afghan and coalition security forces using IEDs, which also incurs casualties to civilians besides killing or injuring security forces.