Senator Foster Ogola of Bayelsa West district in the Niger Delta region said he completed his doctoral studies at Gospel Missionary Foundation, a theological university, in 2012.

He said his PhD was on the topic of Christian leadership.

However no research paper or thesis by the senator exists online.

But Senator Ogola insists his degree is not fake, telling the BBC:

The university does not exist today. [But] it had been graduating students for several years every year... If the university is not accredited that does not make my degree fake."

He says the dispute over his qualification is a politically motivated attempt to discredit him and stop him from running for office again.

The Gospel Missionary Foundation is among a number of universities due to be closed down by the National Universities Commission of Nigeria.