BAUCHI, Nigeria (Reuters) - Twenty people, including children, were burnt to death after a public mini-bus collided with a car on a highway in northern Nigeria, the road safety agency said on Tuesday.

       "The accident was caused by a speed violation. A driver was injured, 20 were killed and burnt to ashes," the Bauchi state command of the Federal Road Safety Corps (FRSC) said in a statement.

       In Africa's most populous nation, many roads are poorly maintained and riven with potholes, leading to accidents that claim dozens of lives every year.

       (Reporting by Ardo Hazzad, Editing by MacDonald Dzirutwe and Sandra Maler)