Superintendent Henry Budhram said the taxi, which was carrying pensioners from Umbumbulu to a paypoint in Eston, was shot at by two pedestrians on Mid-Illovo Road after 8am.
Netcare 911 spokesperson Chris Botha said six people were in the taxi at the time.
He said the two critically wounded passengers were taken to a hospital in Pietermaritzburg for treatment.
The remaining three passengers were counselled a short while after the incident.
Budhram said the motive for the shooting was unknown but police had not ruled out the possibility that it was related to taxi violence.
No arrests had been made yet.
Sapa
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