"No other people were injured in the shooting ... a murder docket has been opened," said Brigadier Thulani Ngubane.
Police were still at the scene when North West Premier Thandi Modise identified the victim as Obuti Chika, the party's regional secretary.
"Police [should] not leave any stone unturned until those responsible are brought to book," she said.
Modise said a number of officials in the province had been the target of violent crime in the past few weeks.
"The provincial government wants to know who is behind these assassinations [and attempted assassinations]," she said. – Sapa