It is one year since about 140 Nigerian oil companies were said to have been paid close to $7bn by the government to import fuel.
Many of those involved did not deliver the fuel and an ongoing government investigation has so far detected that at least $1bn was wrongly paid out to such companies.
Oil and gas executives say the sector is recovering from the damage done to the image of the industry, while the government says it is determined to get the money back.
Al Jazeera's Yvonne Ndege reports from Abuja.
Source: Al Jazeera