A freight train has collided with a truck carrying farm workers at a crossing in eastern South Africa, killing at least 19 people and leaving bodies strewn across the scene of the crash.

"The accident was messy," said a government spokesman, Thulani Sibuyi, adding that heads and limbs had been severed from bodies.

At least two dozen people were injured in the accident in Mpumalanga, an eastern province in South Africa, said an emergency spokesman, Jeff Wicks.

A final death toll is yet to be established.

"You have scattered bodies. It is difficult to count or to come up with a conclusive number," said a provincial spokesman, Joseph Mabuza.

Sibuyi said the owner of the truck was being questioned by the police.

Traffic accidents with high death tolls are common in South Africa, and are often blamed on negligent drivers and badly maintained roads.

In 2010, a man driving 14 children to school evaded barriers at a crossing near Cape Town and a train crashed into it, killing 10 of his young passengers. The driver was convicted of murder over the deaths and attempted murder in the case of the four surviving children. He was sentenced to 20 years in prison. Transportation officials hailed the tough charges and sentence, saying they could help deter reckless driving.