Hundreds injured in train crash in Soweto, South Africa

Witnesses said a commuter train hit a stationary train from behind and that the force threw some of the passengers through the windows.

At least two of the casualties were reported to be in a critical condition.

Officials said it was one of the biggest such rail incidents for years.

South Africa's Railway Safety Regulator (RSR) said it was investigating the cause of the crash, which occurred at 1750 local time (1350 GMT).

Local television news pictures showed casualties being treated at the scene by medics - some of them tended to by torchlight.

"We had a total of two men who were critically injured and airlifted to Charlotte Maxeke academic hospital, and 642 with minor and serious injuries," rescue official Jeff Wicks told the South African Press Agency (Sapa).

Mr Wicks said there had been "chaos" at the scene.

"We had people who were sprayed 200m around the trains... on arrival, paramedics found passengers from both trains lying on the track," he said.

According to Pretoria News, people lay groaning in the dark, with some waiting more than an hour before being transported to hospital.

Synock Matobako, a spokesman for the emergency services, said they had had to request more ambulances due to the number of casualties.

"This is the biggest incident in recent years, even though no one has died. People sustained serious multiple injuries."

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