Nigerian terror accused Henry Okah was denied bail in the Johannesburg Magistrate's Court.
"Your bail application is denied," Magistrate Hein Louw said.
He stated that evidence given by Okah when he took the stand failed to convince the court that he was not the leader of the Movement for the Emancipation of Niger Delta (MEND).
"The most damning evidence is that in a letter written in her handwriting the applicant's wife refers to him as being the leader of MEND," Louw said.
Okah faces terrorism related charges for his alleged involvement in the October 1 Independence Day bombing in Abuja.
Twelve people were killed and 36 were injured in the bomb blast.