At least 45 Egyptians were killed when their bus ran off the road and plunged into a canal south of Cairo on Sunday, a security official said.
At least 60 people were in the public bus when it swerved into the canal to avoid an oncoming truck as it was heading from the capital Cairo to the city of Minya, the official said.
"Forty-five bodies were retrieved from the coach and 12 people were injured, and rescue workers are still working," the official told AFP, adding that the death toll was likely to rise.
Villagers and at least 20 ambulances rushed to the scene after the accident near the village of Bahrut about 200 kilometres south of Cairo, an AFP correspondent at the scene reported.
Poor road conditions and lax traffic regulations in Egypt cause thousands of accidents every year and a new highway code came into force in August with the aim of improving road safety.
Last week, 15 Coptic students were killed when their bus overturned while travelling from Minya to the Mediterranean city of Alexandria.