Transport Minister Joe Maswanganyi says preliminary investigations indicate that the derailment of a Shosholoza Meyl train near Kroonstad in the Free State on Thursday morning was caused by a truck crossing a level crossing.

Addressing reporters at the scene‚ he said 12 people had died and 239 were injured in the accident.

Free State health department officials however put the death toll as high as 20‚ saying the body count could rise.

The train had 429 passengers on board the train which was travelling from Port Elizabeth to Johannesburg..

The train hit the truck‚ causing seven coaches to derail. One of the coaches was a power car which caught alight. Maswanganyi was addressing the media at the scene of the accident on Thursday.

Maswanganyi said he was attending a funeral of a provincial official in Parys when he heard about the accident.

"The accident was as a result of a truck with two trailers driving through a level crossing. He was taking chances. That has caused lots of lives."

Maswanganyi suggested there could be more fatalities as the derailed train carriages were still to be removed from the rail tracks.

Maswanganyi said police were investigating the accident.

He said a truck driver had been taken to hospital. He said blood tests would be taken to see if the driver was sober.

Maswanganyi said the driver would also be questioned about his role in the accident.