JOHANNESBURG - At least 12 people were killed and nine others injured in a mass shooting at an informal settlement in Johannesburg, South Africa's largest city, police said on Wednesday.

The shooting occurred at around 11:10 pm local time (2110 GMT) on Tuesday in the informal settlement of Jumpers in Cleveland, when more than 10 armed suspects entered the settlement and opened fire on residents at multiple locations before fleeing in a vehicle, according to the South African Police Station (SAPS).

Eight men and three women were pronounced dead at the scene, and another male victim died later in the hospital. Nine people who sustained gunshot wounds were taken to medical facilities for treatment, the SAPS said in a statement released on Wednesday.

The motive for the attack remains unclear and no arrests have been made.

The SAPS said an intensive investigation is underway and urged residents to remain vigilant as efforts continue to track down those responsible.