Fifty people have been killed after a train collided with a bus in a city south of the Egyptian capital Cairo.
A senior security official in Assiut, near the crash site, said 48 of the dead were children, aged between four and eight.
One woman and a man, who was the bus driver, also died, he added.
The state news agency said another 15 people were injured. A medical source said as many as 28 were injured, 27 of them children.
"They told us the barriers were open when the bus crossed the tracks and the train collided with it," doctor Mohamed Samir said, citing witness accounts.
He said the bodies of many of those killed were severely mutilated, indicating the force of the crash, which took place in the city of Manfalut, near Assiut, some 190 miles south of the capital.
President Mohamed Mursi ordered his ministers to offer support to the families of those killed.
Transport Minister Mohamed Rashad has offered his resignation, as has the head of the railways authority, which President Mursi was considering, state media reported.
The governor of Assiut, Yahya Keshk, has ordered an inquiry.
Egypt's roads and railways have a poor safety record.
Egyptians have complained that successive governments have failed to enforce basic safety standards, leading to a string of deadly accidents.
Earlier this month, at least three Egyptians were killed and more than 30 injured in a train crash in Fayoum, another city south of Cairo.
In July, 15 people were injured in Giza, close to the capital, when a train derailed.