Salmon Arm RCMP say the shooting happened during an event at the Church of Christ in the community about 100 kilometres north of Kelowna, and investigators do not believe it was religiously motivated.
They say a man entered the church at about 10:30 a.m. and allegedly shot two parishioners.
Police say several parishioners wrestled the alleged shooter to the ground, and officers seized a rifle.
They say one person died at the scene, while the other was taken to hospital in stable condition.
Police say charges against the suspect are pending, and there's no reason to believe there's a risk to public safety.
Investigators say the suspect knew at least one of his alleged victims - neither of whom is being identified.