Post-mortems were being carried out on Wednesday on the seven victims of an SA Roadlink bus crash in Beaufort West, Western Cape police said.
Captain David de Klerk said the death toll had not risen overnight and post-mortems had begun on Wednesday morning.
"National investigators are also expected to arrive today to start investigating the case," he said.
No arrests had been made.
The coach crashed on Tuesday morning while travelling from Johannesburg to Cape Town.
At the time, traffic spokesperson Xenophone Wentzel said there was a possibility the driver had fallen asleep.
SA Roadlink spokesperson Mapaseka Mashele denied this.
She said the bus driver stopped in Beaufort West to pick up a passenger.
Experienced drivers
A short while later, Mashele said the driver tried to give way to a truck that had been tailgating him.
"At this stage, the bus driver was on a piece of gravel road, and it caused the coach to overturn. The driver did not fall asleep."
She said all Roadlink drivers were experienced and had taken advanced courses.
Police said 59 people had been on board the bus at the time and among the dead was a child.
The bus driver was among the injured and had not been arrested.
On Christmas Eve in 2006, an SA Roadlink bus crashed into the pillar of a bridge in KwaZulu-Natal, resulting in the deaths of 12 people.
In another accident in 2008 involving the same national operator in the same province, 11 people were killed.
'Coffins on wheels'
The bus company came under the spotlight several times and KwaZulu-Natal's transport MEC Bheki Cele suspended its licence in the province in January this year.
This led to a war of words between the MEC and the company, which in turn led to court action.
Cele labelled SA Roadlink buses "coffins on wheels" and said it was in the public interest that the buses be pulled off the road.
Later several buses from the Roadlink fleet were found to have defects and impounded.
In February, the bus company offered to send its entire fleet of vehicles to government testing centres.
Spokesperson Jozi Donjeany at the time said it would "be given the stamp of approval and hoped the exercise may put an end to serious allegations against its safety standards".
The court case between Cele and the operator was later withdrawn when the company countered that it was being unfairly singled out.
Sapa
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