At least 29 people were killed when a bus overturned on a road south of the Iranian capital Tehran early on Wednesday, AFP reported according to the official IRNA news agency .
"The number of people dead in today's accident reached 29, while 10 have been injured," the head of city of Saveh's medical network, Habibollah Rezai, was quoted as saying.
The injured were taken to hospitals nearby.
Traffic police Colonel Rasoul Ziaoddin was quoted by the ISNA news agency as saying the accident occurred around 4:00 am (2330 GMT Tuesday) on the road from Tehran to Saveh and that driver fatigue was suspected as the cause.
Roads in Iran, with its 74 million people, are among the most dangerous in the world. According to official figures, around 23,000 people died in car accidents in the 12 months to the end of March, the Iranian year.