The convoy of Governor of Borno State, Kashim Shettima, was involved in a road crash, on Friday, leading to the death of his senior special assistant on protocol, Farouk Farouk.
A driver, who sustained injuries in the accident, has reportedly been taken to an undisclosed hospital.
A source said that the tragic incident occurred along the Abuja Kaduna expressway.
It was not clear if Shettima was on his way to welcome President Muhammadu Buhari who returned to the country after a 49-day vacation in London.
Shettima was not among the governors who were with Buhari at the presidential villa in Abuja.
Spokesman of the governor, Isa Gusau, could not be reached for comments, as his mobile telephone was out of reach.