Corruption can take a major toll on a country's economy. International auditors are warning bribery, fraud, and graft could devour as much as 37% of Nigeria's GDP by the year 2030. But as CGTN's Kelechi Emekalam reports, authorities have found a creative way to shine light on the cost of fraud and graft -- by staging marathons.

A race for a common purpose. These athletes are running, not for gold, but to raise awareness corruption. Marathon is a very popular sport here. And the anti-graft body, the EFCC, is taking advantage of it to spread its anti-corruption message to the masses. The 2017 Corruption Perception Index by Transparency International ranked Nigeria 27, the most corrupt country in the world. It's a slight improvement from the previous year.

IBRAHIM LAMORDE MAGU NIGERIAN EFCC CHAIRMAN "The fight against corruption has come to stay. Don't bring corruption back, I'm telling you, no going back. We are going to fight, and I want to call on you, everybody here, to join in the fight against corruption, because that is the only thing we can do to save this country."

KELECHI EMEKALAM ABUJA "Nigerians will vote their next leaders early next year in a general election. The fight against corruption is expected to remain a topical issue in the campaigns. President Muhamadu Buhari who campaigned on ending endemic corruption is seeking re-election into office -- even though his success against corruption is highly contested by his critics, the anti-corruption message remains prominent is his manifesto. Kelechi Emekalam, CGTN, Abuja, Nigeria."