Kamloops Fire Rescue assistant Chief Brian Lannon says emergency crews were informed of the explosion outside a retail store shortly after 11 a.m.
He says someone used an extinguisher before fire crews arrived and found two patients hurt.
Lannon says one bystander was thrown more than four metres following the explosion.
B.C. Ambulance Service spokeswoman Preet Grewal says the two patients were transported by ground ambulance to Royal Inland Hospital with serious injuries.
Lannon says both patients are in stable condition and the investigation is continuing. (CFJC, Kamloops This Week)
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