More than 30 prisoners and some warders were injured in a bus accident on the M3 in Balgowan near Pietermaritzburg on Friday morning, KwaZulu-Natal police said.

"The prisoners and staff members were injured and rushed to hospital after an accident occurred on the M3 in Balgowan near Pietermaritzburg this morning," said Superintendent Vincent Mdunge.

Mdunge said the driver of the bus lost control of the vehicle because of slippery roads.

"The prisoners were all women. They were travelling between Pietermaritzburg and Durban. All the people have been rushed to hospital," said Mdunge.