Niger Delta Minister Godsday Orubebe told the South Gauteng High Court in Johannesburg that he had no knowledge of Okah's plans.
Orubebe, flown in by the Nigerian government to testify against the accused, gave a grisly account of events that occurred on the eve of the bombing, the day of the tragedy and the aftermath of the explosions. Twelve people died in the explosion and 36 were injured.
"Being the country's independence anniversary, many state presidents and diplomats had gathered at Eagles Square to celebrate the day … Suddenly, two heavy bangs ripped the air. These occurred about 300m away from the venue of the celebrations. Text messages started filtering into our phones stating that two car explosions had just occurred outside the venue with multiple deaths and injuries," Orubebe stated.
Okah, the alleged rebel leader for the Movement for the Emancipation of the Niger Delta (MEND), is facing terrorism charges. He has persistently denied the charges and stayed in custody at the Johannesburg Central Prison since his arrest on October 2 2010, as the court has turned down all his previous applications for bail.
Donning a casual checked shirt, khaki trousers and sneakers, Okah appeared composed in the dock, occasionally chatting away with his defence lawyer, Lucky Molatala and teasing photographers.
"Wait, you would have to first notify me to take a pose so you can get a better picture. Take more," he said.
Police deployed outside court and cordoned off the area near the court building.
Though Okah professes close a relationship to Nigeria's President Goodluck Jonathan and several of ministers including Orubebe, the latter told the court that he had no knowledge of Okah's sinister intentions until the date of the bombings.
"After the bombs went off, I called him four times to inquire whether he was involved and he never picked his phone. I don't know why he didn't pick his phone," Orubebe said.
When prosecutor, Shaun Abrahams, passed on a copy of a document from China Xinsindhai firm, with quotations for several arms, that Okah alleges was given to him by Orubebe, the minister denied knowledge of the document let alone ever seeing it.
"Purchase of arms is a sensitive venture and governments world over have a defence sector charged with executing such purchases. I couldn't have passed such a document to Okah. In any case, I'm neither the minister in charge defence nor finance," Orubebe said.
Presiding judge CJ Claaseh adjourned the case to October 2.
The trial is scheduled to run until December. Prosecutor Abrahams stated he has lined up several witnesses to testify against Okah.