At least 17 people have died in a cholera outbreak in the Hammanskraal township outside South Africa’s capital, Pretoria, authorities said Wednesday.

The toll has risen from an initial 10 fatalities reported by local health authorities earlier this week.

Authorities said there were another 29 laboratory-confirmed cholera cases, while 67 people were admitted to a hospital and clinics for gastrointestinal infections.

Health authorities are yet to confirm the exact source of the cholera outbreak, but poor wastewater management and local government instability in South Africa’s capital city have been blamed for the situation.

The City of Tshwane Municipality, which takes in Pretoria and surrounding areas, has had at least five different mayors since the ruling African National Congress party lost control in local government elections in 2016.