Kyle Syrenne was taken to hospital with life-threatening injuries after the incident on Saturday.
Const. Alex Berube says the dispute happened on the Songhees First Nation reserve in Greater Victoria at about 4:30 a.m.
RCMP say a taxi had just dropped some people off when a physical altercation broke out between a group that included the cab's occupants.
Officers are still trying to identify members of that group and are asking people who were in the taxi that morning to come forward.
Police have not described Syrenne's injuries or disclosed whether a weapon was involved. (CFAX)