Fans were attempting to get in to see the Nigerians play North Korea
Sixteen people, including two policemen, have been injured after a crush outside a South African ground hosting a World Cup warm-up game.
Several fans fell under a rush of people outside the Makhulong Stadium in the Johannesburg suburb of Tembisa.
Entry to the friendly between Nigeria and North Korea was free, and many more than the 10,000 capacity turned up.
Football's world governing body Fifa has said it was not involved in any "operational" aspect of the fixture.
A Fifa statement added that "contrary to some media reports, Fifa had nothing to do with the ticketing of this game".
One fan, Japhta Mombelo, described the moment he was caught up in the chaos.
"The crowd overpowered me and I went down," he said. "I fell down and people just fell over me."
The first crowd surge came when the stadium gates were opened to allow fans entry.
Police soon closed the gates, but when they were re-opened, a second rush occurred, with more people falling over.
"When we were coming in, they were just stepping on us," another fan, Princess Mbali, who was wearing a South Africa shirt, said.
"I thought I was dying. I was at the bottom."
The incidents have provided the wrong sort of build-up to the World Cup that the South African authorities would have wanted
BBC Sport's Piers Edwards
One policeman was seriously hurt after reportedly being crushed against a gate. He remains in a stable condition, according to the South African Police Services.
The crowd was mainly made up of local South African and travelling Nigerian fans.
Police said that hundreds of them were also holding photocopies of tickets and tried to break down the gates after the match had started and police had closed them.
In a separate incident the game was then stopped for five minutes in the second half when a railing collapsed inside the stadium.
The incidents have provided the wrong sort of build-up to the World Cup that the South African authorities would have wanted, the BBC's Piers Edwards, outside the stadium, says.
The venue is not a World Cup venue, but the incident is likely to heighten security even further ahead of the World Cup opener between South Africa and Mexico at Soccer City on Friday, our correspondent says.
The game itself finished 3-1 to Nigeria, with Yakubu Aiyegbeni, Victor Obinna Nsofor and Obafemi Martins scoring for the Super Eagles, while Jong Hyok Cha was on target for North Korea.