Police also said that 45 other people were injured, including five in a serious condition, 10 moderately and the remainder only lightly.
Rescue workers managed to remove several injured passengers trapped inside the bus, which struck a tree after veering off the road.
An investigation was launched to establish the cause of the accident, Schindlova said.
"Two children sustained serious head injuries and were put on artificial ventilation and into artificial comas," said rescue service spokeswoman Jana Postova.
The damaged bus belongs to the private Arriva company and was the link between the 6th district of Prague and the village of Holubice, north-west of the Czech capital.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)