Gunmen armed with rifles and pistols opened fire at people in a bar in South Africa's Soweto township in the early hours of Sunday, killing 15 and wounding nine, police said.
The carnage took place shortly after midnight, when the armed group entered the Orlando East tavern, in the township on the outskirts of the main city Johannesburg, spraying bullets at its patrons, said witnesses and police.
Thobani Mhlabiso, a waiter, hid behind a fridge to survive the onslaught in one of Soweto's poorer neighbourhoods, which is made up mostly of scrap-metal shacks.
"Some were shot in the head, you could see their brains spilling out," the 26-year-old said. "I had to jump over those bodies. There was blood everywhere."
Police confirmed there was a second apparently random shooting at about 8.30pm on Saturday in a tavern in Pietermaritzburg, about 500 kilometres south-east of Soweto, killing four people and wounding eight.
Nqobile Gwala, police spokeswoman for KwaZulu-Natal, which includes Pietermaritzburg, said the force was treating this shooting separately.
"We do not think the incidents are linked because they took place in different provinces," she said.
In each case, the gunmen fled and are now on the run, police said.
"I'm so heart-broken," said Sololo Mjoli, a 59-year-old gardener, whose two sons, Sthembiso, 34, and Luyanda, 18, were killed.
Sthembiso's girlfriend had arrived at the scene shortly after the attack to find him still breathing. He was taken to hospital, but died.
Crowds gathered around the police cordon, where a heavy police presence maintained order and combed the area for clues. One officer carried zip-locked bags full of spent bullet cartridges.
South Africa is one of the world's most violent countries, with 20,000 people murdered every year, one of the highest per-capita murder rates.
Soweto is the largest of the country's black townships. White minority rule which ended in 1994 but its legacy of widespread poverty, youth unemployment and violence persists nearly three decades later.
Elias Mawela, police commissioner for South Africa's most populous Gauteng province, said there had been a third shooting during a suspected robbery in a tavern in Katlehong, also outside Johannesburg, on Thursday night, which killed two people and wounded two others.
Referring to the Soweto shooting, Mr Mawela said: "There was no specific person targeted. You can see by the way the bullet cartridges are cast around that they were just shooting randomly."